341 THE ALPINE GARDENER
Alpine Gardener the
JOURNAL OF THE ALPINE GARDEN SOCIETY
VOL. 83 No. 3 SEPTEMBER 2015 pp. 234-351
the international society for the cultivation, conservation and exploration of alpine and rock garden plants
Volume 83 No. 3
September 2015
Alpine Gardener THE
306 240
CONTENTS 235 EDITOR’S LETTER 237 ALPINE DIARY
A special Alpine Open Day at RHS Garden Wisley; readers’ letters.
240 JOHN GOOD’S DIARY The variety that results from gardening with a butterfly mind.
306 HOW TO GROW IT
Robert Rolfe on Acanthus hirsutus subsp. syriacus.
SPECIAL SEASONAL FEATURE
308 THE ALLURE OF AUTUMN
308
Robert Rolfe looks at the seasonal highlights in a selection of fine gardens.
336 A TRIO FOR SEPTEMBER
Peter Erskine praises three autumn favourites.
340 LATE CROCUSES Robin White relates some experiences with autumnflowering crocuses.
September 2015 Volume 83 No 3
HEPATICAS
250 The surge in the
popularity of this genus shows no sign of abating. In this wide-ranging and in-depth study, Michael Myers surveys and evaluates the species and hybrids in cultivation.
237
297
Then, on page , he looks at their cultivation, in the process consulting key growers to compare and contrast their techniques.
344 PRIZE PLANTS
Splendid exhibits from this year’s Northumberland, South West, Cleveland, Chesterfield, Dublin and Midland AGS shows. COVER PHOTOGRAPHS
FRONT Hepatica acutiloba x nobilis
‘Cremar’ (see page 250). BACK Crocus kotschyanus var. leucopharynx (see page 308).
ON THESE PAGES
LEFT Acanthus hirsutus subsp.
syriacus; Paeonia obovata ‘Alba’; Colchicum autumnale ‘Album’. RIGHT A crevice garden in a trough; Hepatica nobilis ‘Mussel’; Saxifraga ‘Allendale Duo’ exhibited by Mark Childerhouse at this year’s Chesterfield AGS Show.
250 344
Published by the
Alpine Garden Society
The international society for the cultivation, conservation and exploration of alpine and rock garden plants, small hardy herbaceous plants, hardy and half-hardy bulbs, hardy ferns and small shrubs AGS Centre, Avon Bank, Pershore, Worcestershire WR10 3JP, UK Tel: +44(0)1386 554790 Fax: +44(0)1386 554801 Email: ags@alpinegardensociety.net Director of the Alpine Garden Society: Christine McGregor Registered charity No. 207478 Annual subscriptions: Single (UK and Ireland) £33* Family (two people at same address) £37* Junior (under 18/student) £15 Overseas single US$56 £35 Overseas family US$62 £38 * £2 deduction for direct debit subscribers Printed by Buxton Press, Palace Road, Buxton, Derbyshire SK17 6AE. Price to non-members £8.00 Second-class postage paid at Rahway, New Jersey. US Postmaster: send address corrections to AGS Bulletin, c/o Mercury Airfreight International Ltd. Inc., 2323 Randolph Avenue, Avenel, NJ 07001. USPS 450-210.
© The Alpine Garden Society 2015 ISSN 1475-0449
Editor: John Fitzpatrick Tel: +44(0)1981 580134 Email: editor@agsgroups.org Associate Editor: Robert Rolfe Tel: +44(0)1159 231928 Email: robert.rolfe@agsgroups.org Practical Gardening Correspondent: Vic Aspland CChem. MRSC Tel: +44(0)1384 396331 Email: vic.aspland@agsgroups.org Custodian AGS Digital Library: Jon Evans Tel: +44(0)1252 724416 Email: jon.evans@agsgroups.org Custodian AGS Slide Library: Peter Sheasby Tel/fax: +44(0)1295 720502 To advertise in The Alpine Gardener please call or email the AGS Centre (details above) The Editor welcomes contributions of articles and photographs. Please call or email the Editor to discuss relevant formats for photographs before sending. The Editor cannot accept responsibility for loss of, or damage to, articles, artwork or photographs sent by post. The views expressed in The Alpine Gardener do not necessarily reflect those of the Editor or of the Alpine Garden Society. The Alpine Gardener is published four times a year in March, June, September and December.
www.alpinegardensociety.net
Cyclamen hederifolium, one of autumn’s signature plants (see page 308)
O
ver a year ago the Alpine Garden Society started a consultation process with its local groups in the UK and Ireland. The aim was to find out how the Society and the groups could best serve each other, though of course these should not be two separate entities. Groups were asked to give their views on how the Society could be improved, and many useful suggestions were forthcoming. Other ideas were impractical, unfeasible or had already been enacted. Last year, as part of this process, the Society’s trustees asked all groups to provide a list of their members, so that the trustees could learn how many nonmembers were in each group. Why would the trustees want to have this SEPTEMBER 2015
Where now for AGS groups? Editor ’s letter information? Well, the AGS constitution stipulates that groups may have up to 25 per cent non-members. This is in the hope that non-members will join a local group and then be encouraged to become full members of the AGS. But this was clearly not happening. Of the approximately 400 new members that the Society attracts every year, only a handful were recruited 235
EDITOR’S LETTER because they had joined a local group. The Society knows this because we ask new members where they have heard of us and what encouraged them to join. So the trustees guessed, rightly as it turns out, that there was the potential to recruit more members from the groups. Of our 47 groups, only nine have returned a list of members. Of those nine, eight breached the 25 per cent non-members threshold and the other one just reached 75 per cent AGS membership. Thirty-eight groups have not responded to the trustees’ request and in fact some have openly refused to do so. I am not a trustee, and I have no vote in these matters, but from my viewpoint this represents a serious breakdown in liaison between the groups and the parent Society. So where does that leave the consultation process? There is no doubt that if the local groups were being set up from scratch today, the Society would insist on 100 per cent AGS membership. No other similar society in the UK with a local group structure, such as the Hardy Plant Society or Plant Heritage, allows non-members to be members. Many AGS groups would like to get more out of the Society centrally in terms of services and benefits, and the Society would like to offer more. But surely there must also be a willingness among the groups to support the parent organisation? If a request is received from the trustees, groups have a duty to respond in a positive manner. If a group fails to do so, the trustees may have to consider whether that group has a future as part of the AGS. In fact if, as seems likely, the vast majority of groups breach 236
the 25 per cent non-members threshold, the trustees would have to consider whether the current local group system has failed and whether it should be disbanded and started afresh. This could have a knock-on effect in that it could affect the future of some AGS shows. If you are a member of a local group, and you want to see the Society flourish and have a long-term future, please encourage non-members to join. It is now estimated that there are between 800 and 1,200 non-members who are members of local groups. Recruiting just a few hundred of these would make a significant difference to the Society’s financial situation and its future prospects. Local groups that do breach the constitution might like to consider this. Your public liability insurance is paid for centrally by the AGS. If someone was to have an accident at a local group event and instigate legal action against the group, it is highly possible that the AGS’s insurers would not pay out. The fact that a group breaches the Society’s constitution could render the insurance invalid. The group members themselves could then be liable for legal costs and damages. John Fitzpatrick We’d like to hear your views about articles in The Alpine Gardener, and also about your experiences of growing plants or searching for them in the wild. Please write to the Editor at the AGS Centre (address on title page) or email editor@agsgroups.org. THE ALPINE GARDENER
ALPINE DIARY RHS/Tim Sandall
A demonstration of trough planting will be part of the Alpine Open Day at Wisley
H
ave you ever wondered what goes on at a meeting of the Joint Rock Garden Plant Committee? How do the members arrive at their decisions to give awards to plants, and what are the criteria that plants must meet to be worthy of an award? Now you can find out at a special Alpine Open Day at RHS Garden Wisley on Thursday, October 1. Visitors will have the opportunity to sit in on a meeting of ‘Joint Rock’ and listen to its expert members discussing the merits of plants being considered for awards. The day will include talks, several practical demonstrations, a photographic exhibition and other activities at Wisley’s Hillside Events Centre. There will also be plant sales at the Wisley Plant Centre and by
SEPTEMBER 2015
An invitation to attend ‘Joint Rock’ specialist alpine nurseries, as well as guided tours around the Wisley rock garden and behind the scenes of the Alpine Department. Joint Rock is made up of members from the RHS, the Alpine Garden Society and the Scottish Rock Garden Club. Talks on each of the three organisations will be given by Dr Christopher Grey-Wilson, Chair of Joint Rock, on behalf of the RHS; David Haselgrove, President of the Alpine Garden Society; and John 237
ALPINE DIARY RHS/Tim Sandall
Planting gentians at Harlow Carr, where an AGS show wiil be held on October 17
Mitchell of the Royal Botanic Garden Edinburgh, Scottish Chair of the committee. Talks on alpines will be given by Markus Radscheit, Garden Manager at Wisley; Joanne Everson, Team Leader of the Alpine Section at the Royal Botanic Gardens, Kew; Simon Wallis, Assistant Supervisor Alpines and Woodland at Cambridge University Botanic Garden; and John Mitchell, Supervisor of the Alpine Department at RBGE. There will be practical demonstrations of trough making, trough planting and growing from seed. RHS botanists will be on hand to answer questions and there will be an exhibition of alpine specimens from the RHS Herbarium. In the afternoon a question and 238
answers session will be chaired by David Haselgrove. Members of the panel will include Dr Christopher Grey-Wilson, Rod Leeds, Professor David Rankin, Dr Martin Sheader, Ray Drew and James Armitage. Entrance to the event is free, although normal arrangements for access to the garden apply. This year one of the AGS’s four autumn shows will be held at an RHS garden. The show at Harlow Carr in North Yorkshire on October 17 will be the last in the 2015 season, and will be preceded by shows at Kent on September 26, Loughborough on October 3 and Newcastle on October 10, where the show will be held for the first time at Cowell’s Garden Centre, Woolsington. THE ALPINE GARDENER
ALPINE DIARY
From David Philbey, Petersfield, Hampshire
I
f you need to move an old greenhouse, or intend to buy a second-hand one that has been glazed with quarter round, stainless steel glazing clips, then reglazing it will almost certainly pose a problem. Old glass is much more brittle than new, even after just two or three years. The force exerted when a compressed spring steel clip snaps into position may well cause the glass to break. Moreover, older greenhouses from the 1970s to the 1990s had heavier gauge (i.e. thicker) clips fitted than is now the case. These may well break every pane. The difficulty is easily avoided. Before pushing the clip home, insert an ordinary 10 x 1.3cm thin plastic plant label between the shoulder of the clip and the glass, pushing them both together. The label will absorb the shock when the clip snaps into position and afterwards is easily withdrawn. Over the years I have reglazed old greenhouses on a number of occasions. This simple manoeuvre really does work every time. From Allen Hickson, New Zealand
A
t the time of writing I have just finished sowing the last of my AGS seed order and decided that I must write and thank you all for the amazing service! I have been a member for about 15 years and it is always a joy first to choose them, then to receive them, then
SEPTEMBER 2015
An old trick when using old glass Letters to sow them, and then, hopefully, watch them germinate. I am coming to the Chelsea Flower Show in 2016, which will be my fifth visit there, and I always look forward to seeing the AGS display and having a chat with the staff. Perhaps you could let all the members who are involved in any way with the seed exchange know just how very, very much their labour of love is appreciated by one overseas member on the other side of the world. With much thanks and appreciation! From John Hanson, Herefordshire
I
very much enjoyed reading the June 2015 issue of The Alpine Gardener. I thought I would just point out that the genus Gunnera commemorates Johan Ernst Gunnerus and not Ronald Campbell Gunn (page 211). The latter is commemorated by more than 50 Tasmanian plants, but I think that Bishop Gunnerus deserves his one. 239
ALPINE DIARY
John Good’s Diary
Y
ou might assume from the title of this column that it is to be yet another of those articles aimed at encouraging the gardener to focus on, or at least provide a place for, plants that are attractive to butterflies. I have always been a keen amateur lepidopterist, from days long ago in short trousers wielding a tiny net on a very long bamboo cane at the swarms (literally in the 1950s) of small tortoiseshells, peacocks, red admirals and many other species homing in on our neighbours’ Buddleja bush. Nowadays I await anxiously the arrival of the relatively few individuals of a diminishing number of species that turn up in our garden in north Wales. But that is not what this piece is about. In this case the word ‘butterfly’ is used adjectivally in the sense of defining someone whose mind, and hence interests, flits from one desirable ‘flower’ to another. Despite my best efforts to curb this tendency, no sooner do I become interested in one particular thing, be it a dish on a menu, a destination in a travel brochure, or a plant in a nurseryman’s catalogue, than my eye flits down the list for other unknown and perhaps superior delights. The more obscure and unusual the alternatives, the more they generally appeal. So my garden is a cornucopia (some would say a rag-bag) of all that I have seen, coveted and managed to obtain and grow over the years, including some plants that are not by any stretch
240
Indulging the whims of a butterfly gardener of the imagination beautiful, and many that most gardeners would not want to grow. But for one reason or another they appeal to me. Perhaps it is a rarity that completes a set: Daphne kosaninii from Bulgaria, given to me by a Czech friend many years ago, which has flowers that never open but nevertheless produce good crops of bright orange fruits. Or it could be a new hybrid or cultivar that has just ‘turned up’ in the garden and I don’t have the heart to discard it: Rhododendron ‘Bryn Mair’, a putative hybrid between R. racemosum and R. keiskei var. ozawae ‘Yaku Fairy’, appeared spontaneously in the garden of our previous home and is probably no ‘better’ than several others of similar parentage that are readily available. Or it could even be a botanical curiosity with, for example, an unusual pollination mechanism such as the Tasmanian trigger plant, Stylidium graminifolium, or a plant that closely resembles other unrelated species THE ALPINE GARDENER
JOHN GOOD
Daphne kosaninii and, left, Rhododendron ‘Bryn Mair’, two plants that appeal to John Good’s taste for the unusual
as a result of convergent evolution – Muehlenbeckia ephedroides which, as the specific epithet suggests, looks just like an Ephedra but is in a different family. If I had a tiny garden would I still seek out and grow such curiosities? Probably SEPTEMBER 2015
not, but as it is I have the room to indulge this mildly eccentric interest, having the plausible excuse to fall back on that, as a botanist, such behaviour is only to be expected! So, apart from developing what I hope 241
ALPINE DIARY
A ‘carefully contrived’ moraine bed in mid-June in John Good’s garden
is an interesting and attractive garden layout, with quite carefully contrived features to satisfy the needs of a wide range of plants, there is not much design involved in the planting. I acquire plants that I fancy, sometimes after a prolonged search, but often on a whim at an AGS show, at a nursery or (best of all) in a generous friend’s garden, with little or no prior consideration about how or where they will fit into the garden. When I get home I generally walk around with the new acquisition in one hand and a trowel in the other, seeking what I believe (or hope) to be the best place for the plant in question, more or less regardless of any aesthetic considerations of colour combinations, continuity of interest or the like. The one thing I do take into account 242
as a result of previous bad experiences is the growth rate and potential space requirement of a new addition, and hence its possible adverse impacts on its new neighbours. Seeing a plant rapidly outstripping the growth of those around it and requiring frequent pruning or, even worse, premature removal, is never satisfactory. In this regard it is best not to trust the descriptions of eventual size in catalogues or on labels unless you are pretty sure they are likely to be accurate. They are almost always understated: for ‘10cm high x 50cm spread in ten years’ read 15cm high x 75cm spread in five years! You can often gauge potential size for yourself by looking at a plant and seeing what growth it has put on in the nursery and comparing it with a THE ALPINE GARDENER
JOHN GOOD
Above, the Saxifragaceae member and American native Telesonix jamesii drapes itself over the wall of a raised bed. Right, the exuberant blooms of Alstroemeria presliana
similar plant you already grow. A glance at the price on the label may also be informative – slow growers are rarely cheap, for obvious reasons. Of course, some plants are so choice or rare (or both) that you may well be prepared SEPTEMBER 2015
to give them more space than their less exalted neighbours. I love alstroemerias, which can spread underground at an alarming rate when happy. But when A. presliana bursts into bloom in late June, all is forgiven; or Telesonix jamesii (the 243
ALPINE DIARY
Arisaema candidissimum doing well under a pine tree in John Good’s garden 244
THE ALPINE GARDENER
JOHN GOOD genus name sounds like a pop group or an IT company, doesn’t it!), rambling across and through the wall supporting a raised bed. Talking of alstroemerias reminds me of another strong ‘butterfly’ tendency exhibited in my gardening – that of hopping from genus to genus over the years. One year I will grab the excellent AGS and other seed lists as soon as they drop through the letter box (or nowadays bring them up online) and click on every Alstroemeria. The next year perhaps all the lilies will be chosen, or all the penstemons, especially those I have never heard of or (extra allure!) those of which the seed has been collected in the wild. This may well take up the whole of my allocation of seed packets, but that is of little concern. Perhaps I might end up with, say, 25 alstroemerias, all duly sown and (my general rule) not more than ten of each that germinates pricked out. Some will be lost between this stage and eventual flowering in pots or in the garden two to three years later. Of those that make it, quite a few will be reluctantly classed as ‘not garden worthy’ for various reasons such as being too large or thuggish, having flowers of poor colour or size, lacking hardiness, or being a poor ‘doer’ in my garden. They will be discarded, though not in the compost bin for this may lead to them being spread all around the garden. A few will be left for another year or two before a further assessment, and perhaps three or four of those will be accepted as permanent residents. And so it goes on, although this particular butterfly gardener has noticed a gradual SEPTEMBER 2015
The ‘whipcord’ Arisaema tortuosum
decline in the will and energy to flit between genera in this comprehensive way in recent years. So now it has become more a matter of filling in gaps within favoured genera, among which are dwarf Ericaceae of all sorts, species peonies, saxifrages, campanulas, dianthus, primulas (especially European species and hybrids), pulsatillas, daphnes, trilliums and, of course, snowdrops. Oh, and arisaemas. There, I have ‘come out’ as a late convert to this genus which divides alpine gardeners between ‘lovers’ and ‘haters’– few just ‘quite like’ them. I was pretty firmly anti-arisaema until one of those kind friends I spoke 245
ALPINE DIARY about earlier gave me a couple of tubers of Arisaema candidissimum, which I regard as the queen of the tribe. Duly planted in humus-rich soil under the quite dry shade of a large old black pine, and top-dressed annually with pine litter and garden compost, they settled down and have slowly increased so that now I have a nice clump from which I am able to remove a few side tubers for propagation or gifts from time to time. I was hooked and began to acquire more species, initially by growing them from seed – few were available in the trade at that time and they tended to be expensive – and latterly by swapping, so that by now I have a reasonable collection, but I am always on the lookout for additions. I grow them unprotected only in the open garden and some have been as lacking in winter hardiness as their origins might suggest, but others have thrived and the often late arrival of their new shoots above ground is awaited with nervous anticipation. Apart from A. candidissimum the longest ‘stayers’ have been various forms of the North American A. triphyllum, with varying degrees of striping on the spathe, a large and vigorous form of A. consanguineum kindly given to me by Mary Randall, a smaller and more refined but no less vigorous A. ciliata subsp. liubaense from wild-collected seed from Liuba in Sichuan, China, and A. tortuosum, the so-called whipcord cobra lily by virtue of its long, thin, erect spadix tip. Lest you should think that my butterfly tendency as a gardener is limited to alpine and woodland plants, I must disabuse you. It extends to all my 246
Dactylorhiza x grandis, which John Good received as a gift during a visit to Ireland
gardening interests, which are many and varied. I have at one time or another, generally simultaneously, grown anything that took my fancy and could reasonably be accommodated in my mild but wet and windy garden, or in my limited area of unheated glass. If I had more room I would grow far more trees – one of my regrets is that I have never had the space to develop an arboretum – and large shrubs. I have a fair range of rhododendrons, big and small, but would like more, especially the species. I have tried quite a few hardy ground orchids over the years, including some of THE ALPINE GARDENER
JOHN GOOD the cypripediums that are now becoming much more freely and cheaply available, but with very limited success. I believe this is mainly due to the depredations of honey fungus (Armillaria mellea), which was a real problem when we first arrived here, thriving on the stumps of trees which had been felled by a previous owner, and which still occasionally kills or maims susceptible plants, including some rhododendrons. Perhaps surprisingly, on first consideration, it also attacks herbaceous plants, including bulbs. I have lost good clumps of various Narcissus species and hybrids in the past. I have found the only cure to be time and the prompt removal of any dead or obviously dying plants and (as far as possible) the complete removal of tree stumps at the time of felling. For now, as far as ground orchids are concerned, I have to be satisfied with thriving clumps of Dactylorhiza fuchsii ‘Bressingam Bonus’, which cropped up naturally at Bressingham Gardens in Norfolk and which increases rapidly and is easy to divide. I also have a particularly nice form of the natural hybrid between D. praetermissa and D. fuchsia (D. x grandis), with heavily blotched leaves, which I was given by a kind lady – whose name I have sadly forgotten – on a visit to Ireland 15 years or so ago. Beware of virus in these orchids. I had a thriving group of the Madeiran D. foliosa that developed the typical distorted leaves and reduced vigour, weakening the plants to such an extent that they had to be consigned to the bonfire. While on the subject of orchids, I have a very small glasshouse in which I try to grow (and I do mean ‘try’ – I SEPTEMBER 2015
Dactylorhiza fuchsii ‘Bressingham Bonus’ 247
ALPINE DIARY
A late-flowering form of Paeonia anomala from the Pamir-Alai
am not very successful) a few that need cool or intermediate temperatures. I have a small fan-heater that keeps the temperature above 15C all year. I grow mostly species as I find the infinite range of form and colours of orchids, not to mention their varied and often bizarre pollination mechanism, intriguing. Also it is nice to have somewhere to enjoy plants in a warm and comfy atmosphere in midwinter. ‘Why not an alpine house,’ I hear you say. Well, I have a small one and I used to grow quite a few plants in it in pots for showing, but that was when I had a smaller garden and a good deal more energy. I use it now principally as a display area for a limited range 248
of bulbs that are grown in an Access frame, although one side is a raised tufa bed with a few nice plants including the beautiful dwarf form of Paeonia cambessedesii, a gift from Brian Burrow. It seems happier there than the second of Brian’s seedlings which I planted out in a sunny raised bed. I am still deeply hooked on species peonies. I grow hardly any hybrids, not because I don’t like them but because I can easily see them in other gardens, and the fact that I am growing a wild species in my garden has a special appeal. I also enjoy learning about (and in some cases visiting) the places and habitats in which they grow. The flowering of each species, particularly if it is for the first time here, THE ALPINE GARDENER
JOHN GOOD
The highly scented Paeonia obovata ‘Alba’, the ‘queen’ of white-flowered peonies
arouses a feeling of eager anticipation, and I almost will the blooms to unfold their invariably gorgeous petals. The season is quite long, starting with P. cambessedesii in late March and ending with a late form of P. anomala from the Pamir-Alai, which is in full flower in late June. A recent and treasured acquisition is a gift from Ron Beeston. P. mascula subsp. arietina ‘Alba’ was derived from vegetatively propagated material from a plant in Sir Frederick Stern’s garden in Highdown, West Sussex, and was presumably grown from seed collected in the wild. It produced one lovely flower last year and one again this, but it looks healthy and will I hope go on to SEPTEMBER 2015
greater things. But I doubt that even this will displace P. obovata ‘Alba’, in my eyes the queen of white-flowered peonies and one that radiates the sweetest of sweet perfumes, from the pedestal upon which I have placed it. So where will my butterfly mind lead me next? Advancing years suggests that it would be prudent to home in on plants that do not take too long to give of their best, although short-lived plants have generally not appealed to me much. But then I am reminded of Dr Simson Hall of Edinburgh, whom I met when we lived there in the 1970s. He was still crossing rhododendrons in his eighties with the earnest hope and intention of seeing them flower! 249
HEPATICAS
Enchanting hepaticas T
here can be no doubt that hepaticas are increasing in popularity. In 1988 The Plant Finder listed four species and seven varieties. Today all the known species are in cultivation and, with the exception of H. falconeri, are available from the trade. The range of cultivars offered for sale has grown significantly, especially those involving H. japonica, which were virtually unknown 25 years ago. In 1990 only one hybrid was recognised but now most of the species have been crossed with one another. In this wide-ranging article, illustrated by his own photographs, Michael Myers surveys and critically evaluates the species and hybrids in cultivation, concentrating on that which is novel and generally unpublished, while
250
the taxonomy of the genus is reviewed with regard to its impact on breeding programmes. Michael, who studied hepaticas as part of a Master of Horticulture (RHS) degree, also THE ALPINE GARDENER
THE OVERBERG
looks at their cultivation and has visited key growers to compare and contrast their techniques (RHS Garden Wisley, Ashwood Nurseries, Glenn Shapiro’s National Collection, Edrom SEPTEMBER 2015
Nurseries, John Mercer and Anne Wright). His study is a snapshot of hepaticas in 2015 and provides an essential reference point for all those who are captivated by these beguiling plants. 251
HEPATICAS
I
n 1990 I wrote a review of the genus Hepatica for this journal (volume 58, pages 144-156). Since then the genus has seen a remarkable surge in popularity, due largely to the introduction of spectacular cultivars from Japan. Growing techniques have been modified as enthusiasts have become more familiar with the plants, while the introduction of ‘new’ species from Asia has posed taxonomic problems for botanists. The new introductions have been complemented by the efforts of hybridisers in Europe such as Marlene Ahlburg, Severin Schlyter and Robin White. John Massey at Ashwood Nurseries has demonstrated that crosses between conceivably all the species are achievable, leading to exciting breeding possibilities. Recent key events for the genus include the publication of Hepatica: Leberblümchen by Andreas Händel and Josh Westrich (there is an English translation planned), the Hepatica 2014 event at Birmingham Botanical Gardens and the introduction of H. falconeri into cultivation in the UK. Plant taxonomy is in many ways a subjective science, although recent advances in DNA analysis are improving our understanding of the relationships between closely related species. Different authors have elevated or demoted Hepatica ‘species’ and as yet no definitive work has taken a holistic view of the genus and the relatedness of its dozen or so species. In 2010 the Dutch botanist Ben Zonneveld produced a reasoned argument for the adjustment of some ‘species’, but some of his conclusions
252
Andreas Händel signing his book at Birmingham Botanical Gardens
are controversial. My aim is to review the current literature in an attempt to interpret some taxonomic issues and present a clearer taxonomic status of the genus since this in turn has important consequences in understanding hybridity and cultural requirements. Until recently all hybrids were lumped into H. x media but, clearly in light of recent research, the validity of this name depends on the status of the parent plants. H. x schlyteri is the only other validly published hybrid name (Mathew & Massey, 2010) and so it is likely that THE ALPINE GARDENER
HEPATICAS
The Hepatica house at Ashwood Nurseries in the West Midlands, where John Massey has undertaken extensive work to create new hybrids
further hybrid designations will be required to distinguish some of the new crosses. The clarification of species and their hybrids may also improve our understanding of the required growing conditions. Hepaticas are expensive plants and so a detailed treatise on how to grow them successfully is long overdue. For several years, until 2009, I held a National Plant Collection of Hepatica and, of the three collections I held during that time, it generated by far the most interest. Hepaticas have been featured in the national press, in SEPTEMBER 2015
books, have formed award-winning displays at RHS shows and make regular appearances at AGS shows. Several have received awards from the RHS including H. nobilis AGM (1993) and H. transsilvanica AGM (1993). This increased popularity reflects their improved availability and their relative ease of cultivation for non-experts. Hellebores have seen a remarkable surge in popularity as garden plants and while hepaticas are not as showy there is no reason why they should not be more familiar to gardeners. It seems 253
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An impressive display by Ashwood Nurseries at the Birmingham Botanical Gardens 254
THE ALPINE GARDENER
HEPATICAS appropriate, therefore, to look at how our understanding of this small group of woodland herbs has developed since my article in 1990.
The genus Hepatica
Hepatica is a small genus of six to 12 species depending on the authority cited. The genus is closely allied to Anemone in the buttercup family, Ranunculaceae. The most obvious difference between Hepatica and Anemone is the presence of an involucre of bracts immediately below the flower in Hepatica, whereas in Anemone it is much further down the pedicel. The showy ‘petals’ are, strictly speaking, sepals. Some authorities have split the genus into two distinct sections. In 2010, Ben Zonneveld proposed the following: Section Hepatica (mainly diploid species, 2n=14, 3-lobed leaves, usually entire margins): H. americana, H. acutiloba, H. asiatica, H. japonica, H. insularis, H. pubescens, H. maxima and H. nobilis. Section Angulosa (mainly tetraploid species, 2n=28, 3-5 lobed leaves, crenatedentate margins): H. falconeri, H. henryi, H. transsilvanica and H. yamatutai. The two sections suggest relatedness between the species within each section. However, it seems implausible that the three tetraploid species (H. henryi, H. transilvanica and H. yamatutai) are more closely related to one another than to geographically closer diploid species from which they may be derived. H. pubescens is also a polyploid but has clear affinities with H. japonica. Zonneveld argues that H. henryi, H. transsilvanica and H. yamatutai are the SEPTEMBER 2015
result of hybridisation with H. falconeri (allotetraploids) while H. pubescens occurred through spontaneous doubling of the chromosomes in H. japonica (autotetraploid). Several species are lumped or split by different authorities and as yet there is no definitive taxonomic treatise. Zonneveld has suggested combining the two American species to create H. americana and H. americana subsp. acuta, based primarily on similar genome sizes, a view shared by Martin Pfosser et al in a 2011 paper. Morphological and ecological differences, however, support some degree of taxonomic separation. Four of the Asiatic species are also combined by Zonneveld to create H. asiatica subsp. asiatica, H. asiatica subsp. japonica, H. asiatica subsp. insularis and H. asiatica subsp. pubescens. These Asiatic species, along with the American ones, are now considered to be genetically distinct from the European H. nobilis. Pfosser et al suggest that H. asiatica and H. insularis are closely related but distinct from the Japanese species, and further that H. maxima may have evolved from H. asiatica. Some Chinese authorities support the view that H. henryi and H. yamatutai are the same, but this is contradicted by Zonneveld. One species, H. falconeri, may be considered to be a link between Hepatica and Anemone on account of the position of the involucre. Zonneveld discusses how it might be a parent of the tetraploid species due to its geographical proximity to them, its crenate leaves and its cumulative DNA values when crossed with H. asiatica. 255
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H. nobilis H. transsilvanica H. americana H. acutiloba
H. falconeri
H. asiatica H. insularis H. maxima
H. henryi H.yamatutai
H. japonica
Geographical distribution of Hepatica adapted from Pfosser et al (2011)
For this article I will maintain the traditional view of the species until further evidence can categorically suggest otherwise. Hepatica nobilis var. glabrata var. pyrenaica Hepatica transsilvanica Hepatica acutiloba Hepatica americana Hepatica asiatica Hepatica falconeri Hepatica henryi Hepatica insularis Hepatica japonica f. japonica f. magna f. variegata Hepatica maxima Hepatica pubescens Hepatica yamatutai
Distribution and ecology
Hepaticas are found in temperate woodlands in the northern hemisphere. They flower in early spring in the wild, after snowmelt but before deciduous trees come into leaf. Of the two European species, H. nobilis has a wide distribution (excluding the UK), growing in mostly 256
deciduous woodlands from sea level to 2,200m depending on latitude. It is also found in woodland fringes and meadows where summer shade is provided by grasses and other herbs. H. nobilis var. glabrata is restricted to mixed woodlands in central Sweden. H. nobilis var. pyrenaica is found on slopes in deciduous (Fagus species) and coniferous (Pinus species) forests in the Pyrenees. It is also found in more open positions. The endemic H. transsilvanica is restricted to parts of Romania on dry slopes in mixed forests. The American species are native to the eastern states of the USA and into Canada. H. acutiloba is generally found in damper conditions in basic soils while H. americana tends to grow in mixed deciduous and coniferous woods in acid soils. In Asia three species – H. asiatica, H. henryi and H. yamatutai – are found in China, the latter two having very restricted distributions in central China (Chongqing and Mount Emei respectively), while H. asiatica is widely distributed in deciduous woodlands in parts of eastern China. H. yamatutai is said to grow in evergreen woodlands (Castanopsis species) at 1,100-2,100m, THE ALPINE GARDENER
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Alpine meadows in Slovenia, where Hepatica nobilis can be found
while H. henryi is more typically found in deciduous woodlands but also among bamboos at 1,400-1,800m. H. asiatica is also found in Korea, which is home to two other species. H. insularis is found in southern parts of Korea and several offshore islands in deciduous woodlands and high meadows, while H. maxima is restricted to the island of Ullung-Do (Dagelet) where it grows in deep shade, often under Rhododendron species. Interestingly frosts are uncommon, with only moderate snowfall in winter. In Japan H. japonica is found on the islands of Honshu, Shikoku and northern SEPTEMBER 2015
Kyushu growing in mountainous regions. H. japonica f. variegata is restricted to the north-east and H. japonica f. magna to the north-west. The tetraploid H. pubescens is found along the southern spine of Honshu. The Japanese hepaticas are separated by morphological characteristics that are of debatable taxonomic importance. H. pubescens may be no more than a tetraploid form of H. japonica (from which it is clearly derived) demonstrating ongoing speciation. H. falconeri is a woodland species found in Kashmir, the Tien Shan and Pamir mountains. 257
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The flowers of Hepatica nobilis vary from white through shades of pink and blue
The European Species Hepatica nobilis var. glabrata var. pyrenaica Hepatica transsilvanica
Hepatica nobilis
H. nobilis is widespread in Europe where it grows mostly in deciduous woodlands but occasionally under pine and spruce. The flowers vary from white through shades of pink and blue, although in some populations single colours dominate. The trilobate leaves, which can persist through the winter, are occasionally marbled (especially in H. nobilis var. pyrenaica). Numerous selections have been made for flower colour, flower form (such as doubles) and leaf pattern (for example, ‘Marmorata’). Despite the natural variability of H. 258
The trilobate leaves of Hepatica nobilis
nobilis, two varieties are recognised which show morphological uniformity and a restricted geographic range. H. nobilis var. glabrata is a diminutive variant, 8-10cm tall, found in southern Sweden. It has hairless, pale green leaves and white flowers. This naturally occurring variant is distinct from ‘compact’ forms of H. nobilis offered in THE ALPINE GARDENER
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Hepatica nobilis var. glabrata is found in southern Sweden
The marbled leaves of Hepatica nobilis var. pyrenaica take on a purple hue in sun
cultivation, which have hairy leaves. As a garden plant, H. nobilis var. glabrata has little to recommend it over more showy and easier relatives. Enthusiasts will want it as part of a collection, and in my experience it is better in a pot or trough outside due to its small stature. H. nobilis var. pyrenaica is a variant found in the Pyrenees, distinguished by SEPTEMBER 2015
the heavily marbled leaves and flowers that are either white or pastel shades in pink and blue. John Massey and John Mercer both report that this species often grows in more open positions on steep grassy slopes. It seems more tolerant of light in the summer, the leaves often taking on a purple hue. It is not unreasonable to speculate that 259
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The showy Hepatica nobilis var. pyrenaica ‘Stained Glass’ at Ashwood Nurseries
the marbling and other pigmentations perform the function of protecting the leaves in strong sunlight. H. nobilis var. pyrenaica is an excellent garden plant and several selections have been made, usually as seed strains that show some degree of uniformity. ‘Apple Blossom’ has pale pink flowers and is offered by several nurseries in the UK. Ashwood Nurseries has recently introduced Cliff Curtis’s H. nobilis var. pyrenaica ‘Stained Glass’. This is an exceptional foliage form, and it is interesting to speculate how long it will be before an entirely silver-leafed cultivar is raised – much in the manner of Cyclamen coum and C. hederifolium. H. nobilis var. pyrenaica is an important 260
parent in breeding programmes, both intraspecific and interspecific. Several notable new cultivars have already been raised from this variety including ‘Hazelwood Froggie’ and Ashwood selections of H. x schlyteri. H. nobilis is the most commonly cultivated species in Europe. It may have been grown initially as a medicinal plant, as its common name of liverwort implies, but it has certainly found favour as an ornamental since at least the early 17th century and was grown in a variety of forms through Victorian times into the 20th century. Good colour forms with large flowers have been selected and named including ‘Angela’, ‘Crawley Down’, ‘Flamingo’, ‘Glebelands’ and THE ALPINE GARDENER
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Hepatica nobilis ‘Walter Otto’ in Andreas Händel’s garden
‘Jean’, but most of these no longer persist in cultivation. On the continent several wild collected colour strains were introduced by Marlene Ahlburg using the ‘Elkofener’ prefix, though Händel and Westrich give the source as Roger Poulet. Various other growers have introduced named cultivars of H. nobilis but invariably they are similar to existing colour forms. Speckled and striped forms are occasionally encountered but are scarce in cultivation. Introductions by the late Severin Schlyter were frequently given names that were abbreviations of their characteristics, hence ‘Bibo’ (blue inner, blue outer). In their book Händel and Westrich provided a comprehensive list of cultivars in cultivation in Europe, SEPTEMBER 2015
some of which are more distinct than others. There seems little value in naming plants that cannot be easily vegetatively propagated. Therefore seed strains that demonstrate uniformity, but which can be improved through breeding, must surely offer the best solution, much as they have done for hellebores. The exceptions would be double forms which are mostly sterile (the additional ‘petals’ are produced at the expense of the sexual organs). Double hepaticas have been grown since the early 17th century and John Parkinson refers to several types in Paradisi in sole Paradisus terrestris (1629). The most commonly encountered double is ‘Rubra Plena’ 261
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Flamboyant fully double and sterile flowers are produced by Hepatica nobilis ‘Mussel’
since it bulks up quite well. The dark pink flowers fade as they age and, like many doubles, tend to droop over. Most if not all the doubles in cultivation are likely to have been wild collected. One possible exception is the ‘anemonecentred’ ‘Little Abington’, which was introduced by the late Rev. Richard Blakeway-Phillips. It is possibly no 262
longer in cultivation since the stock seemed to be virused, although this did not affect flowering. On the Continent numerous double forms have been selected and named. My personal favourite, which still persists, is ‘Walter Otto’. In 1997, on a visit to Andreas Händel’s garden, I saw it lined out in the manner of spring bedding. THE ALPINE GARDENER
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The semi-double Hepatica nobilis ‘Tausendschön’
Händel and Westrich refer to numerous double clones including pinks, blues and whites. Most of these plants are confined to collections. The vast majority are fully double and so completely sterile, as seen in ‘Mussel’, but some semi-double forms such as ‘Tausendschön’, introduced by Andreas Händel, retain stamens and carpels and so offer tantalising possibilities for breeding new double forms. New cultivars must offer something different from the existing ones, and one of the most important breeders of recent years was Severin Schlyter. Two double forms introduced by him are ‘Schlyter’s Double White’ and ‘Schlyter’s Little Red’. SEPTEMBER 2015
His major contribution to hepatica breeding is undoubtedly the introduction of unusual leaf forms, which provide added interest when the plants are not in flower. While hepaticas are unlikely ever to rival heucheras for foliage interest, it is an area where improvements could be made. Schlyter’s H. nobilis ‘Cremar’ has unusual scalloped leaves with attractive marbling. It was derived from a cross between ‘Crenatiloba’ and ‘Marmorata’ but it can be raised directly from seed since a high proportion, up to 100 per cent, come true to type. ‘Cremar’ has also been used by John Massey as a parent for Ashwood selections of H. x schlyteri. 263
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Hepatica nobilis ‘Schlyter’s Little Red’ at Ashwood Nurseries
A more recent introduction is H. nobilis ‘Papilion’, which shows some degree of variability but usually the leaf lobing is accentuated, with scalloping along the margin. Another peculiar leaf selection from Taavi Tuulik in Estonia is ‘Monoloba’, where the normally trilobate leaves are unlobed. There is a suggestion that unusual flower and leaf forms occur in areas with high levels of radioactivity, whether naturally or otherwise. The Chenobyl disaster is implicated in the wide range of double forms of Anemone ranunculoides currently being found. Certainly many of the Ranunculaceae demonstrate a high degree of plasticity in flower form, which could be accentuated by radiation. 264
The leaves of Hepatica nobilis ‘Cremar’ THE ALPINE GARDENER
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Typical leaves of Hepatica transsilvanica, though there are many variants
Hepatica transsilvanica
H. transsilvanica is endemic to Romania although John Massey has received unsubstantiated reports of it growing in Russia. It is found primarily in mountainous regions growing under beech (Fagus sylvatica), oak (Quercus petraea) and sycamore (Acer pseudoplatanus). H. transsilvanica is tolerant of dry conditions and is unusual in being the only Hepatica species to spread significantly by vegetative means. It has crenately lobed leaves although numerous leaf variants have been described in the wild. H. transsilvanica is a tetraploid species and does not set as much seed as H. nobilis. The creeping habit of H. transsilvanica facilitates the SEPTEMBER 2015
easier propagation of colour forms by division, and this same characteristic and its ease of growth makes it a useful parent for hybridisation. In the wild H. transsilvanica is mostly blue and indeed most named selections are in varying shades of blue. For example, ‘Loddon Blue’ (pale blue), ‘Ada Scott’ (dark blue), a selection from Paul Christian listed as dark form (pictured overleaf), ‘Supernova’ (dark blue) and the early flowering ‘Winterfreude’. A vigorous mid-blue form introduced by Marlene Ahlburg is ‘Karpatenkrone’, while the recently selected ‘Blumenstadt Erfurt’ from Andreas Händel looks promising since it can start flowering at Christmas. The most vigorous form of 265
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Hepatica transsilvanica (dark form)
Hepatica transsilvanica ‘Supernova’
Hepatica transsilvanica ‘Eisvogel’
Hepatica transsilvanica ‘Lilacina’
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Left, from top, flower development of Hepatica transsilvanica ‘Connie Greenfield’ showing variation with age and, right, of H. transsilvanica ‘Elison Spence’
H. transsilvanica that I grow is another German selection called ‘Eisvogel’. This has white flowers with a blue flash on the reverse; the leaves also have a purplish tinge to the reverse. The pink flowered ‘Lilacina’ is a lovely selection that is often SEPTEMBER 2015
seed-raised and so is variable. Plants offered as ‘Rosea’ are the same thing. It is suggested that some selections of H. transsilvanica are actually hybrids with H. nobilis, with which it hybridises in the wild. One of the most 267
HEPATICAS significant introductions in recent years is ‘Harvington Beauty’ from the Worcestershire nurseryman Hugh Nunn. This vigorous and floriferous form has generally been offered as H. x media. However, work on DNA content by Ben Zonneveld would suggest that rather than being a triploid, suggesting hybridity, it is a tetraploid as is H. transsilvanica. Zonneveld suggests that ‘Harvington Beauty’ is a cross between H. transsilvanica and H. yamatutai but this seems highly improbable. John Massey has provided an alternative suggestion, in that Ernest Ballard had relatives living at Harvington in the early 20th century and it may be that the plants found by Hugh Nunn in a garden there are a relic from Ballard’s hybrids. Nunn reports that ‘Harvington Beauty’ can produce seedlings resembling H. nobilis despite no other hepaticas being grown in the vicinity. H. transsilvanica has also produced several double forms. In the UK the cultivars ‘Connie Greenfield’ and ‘Elison Spence’ are considered to be distinct but flowers on both can be highly variable, especially as they age. John Massey has stated that ‘Elison Spence’ has flatter petaloid stamens than ‘Connie Greenfield’.
The American species Hepatica acutiloba Hepatica americana
Hepatica acutiloba
This is an evergreen closely allied to H. americana and included within this species by some authorities. The specific 268
name describes the sharply lobed leaves and involucre, one of several characteristics that distinguish it from H. americana. The upright flowers and hairy, bronze-tinged new foliage make this an attractive plant for pot culture. Perversely, in 1919 Reginald Farrer described the species (as Anemone acutiloba) as ‘a North American of no merit’. In the wild it grows in calcareous THE ALPINE GARDENER
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The flowers of Hepatica acutiloba, right, are most often seen in white, though pale blue and pink forms are not uncommon Opposite top, the hairy, bronzetinged new foliage of Hepatica acutiloba and, below, a sharply lobed mature leaf
mountain woodland in the eastern USA. Where H. acutiloba overlaps with H. americana, intermediate forms exist. Some plants have a strong fragrance, a characteristic that would be desirable in breeding not only within the species but through hybridising with others. John Massey reports that H. acutiloba grows in damper, richer soils than H. americana, often alongside streams. SEPTEMBER 2015
This attractive species is most common in its white-flowered form although pale blue and pink forms are not uncommon. Darker blues include ‘Eco Regal Blue’ from Don Jacobs, who has selected several forms, all with the ‘Eco’ prefix. Double forms including ‘Louise Koehler’ and ‘Eco White Fluff ’ have been selected but are rare in cultivation. John Massey also refers to ‘Elkin’s 269
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Hepatica acutiloba ‘Louise Koehler’ and, below, a pink form of the species
Double’, which was found in Detroit, Michigan, in a woodland which no longer exists. This cultivar has pale blue sepals that are greenish in the centre. Another cultivar found in Michigan is ‘Sanford’ with pale, blue-purple flowers and tepals more pointed than in ‘Louise Koehler’.
Hepatica americana
The second American species has rounded, trilobate leaves and is typically found in mixed deciduous and coniferous woods on acid soils in the eastern states of the USA. It is said to prefer drier conditions than H. acutiloba. The evergreen leaves can be attractively 270
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HEPATICAS
Hepatica americana ‘Ashwood Flare’
Hepatica asiatica flower
marbled, a characteristic that has led to selections including ‘Eco Indigo’, ‘Eco Blue Harlequin’ and ‘Ashwood Marbles’. Pastel blues and whites are most common but a recent selection by Ashwood Nurseries is the reverse picotee ‘Ashwood Flare’.
The Asiatic species Hepatica asiatica Hepatica falconeri Hepatica henryi Hepatica insularis Hepatica japonica Hepatica maxima Hepatica pubescens Hepatica yamatutai
Hepatica asiatica
A deciduous and usually whiteflowered species from eastern China and Korea. The flowers are held on long, hairy stems and appear before the new foliage. The foliage is typically trilobate and may be slightly marbled. This species is quite widespread and has several disjunct populations. SEPTEMBER 2015
Hepatica asiatica leaf
The South Korean populations have probably provided most of the plants in cultivation but it also occurs in North Korea, north-east China and eastern China. These populations may provide greater diversity in the future. John Massey reports that 99 per cent of plants seen by him in South Korea were white.
Hepatica falconeri
This deciduous species from Jammu and Kashmir, northern Pakistan and Kyrgyzstan is new to cultivation in the UK. It is often described as a missing link since it exhibits characteristics of both 271
HEPATICAS Anemone and Hepatica. H. falconeri is a small plant with deeply divided, threelobed leaves with paler markings. The small, white flowers can have a red flush on the reverse. They are borne in spring on straight stems. The involucre, which is immediately below the flower in other hepaticas, is about 8mm below the flower in H. falconeri. The species has been grown on the continent for a few years but as far as I am aware has only just come into cultivation in the UK at Ashwood Nurseries. H. falconeri has been implicated as a parent of H. henryi, H. transsilvanica and H. yamatutai due to the trilobate leaves that have entire or incised to dentate lobes, a characteristic seen in the three tetraploid species. The genome size of H. falconeri (a diploid species) is smaller than that of any other species of Hepatica, but when combined with the genome size of H. asiatica produces a genome size that is not dissimilar to the three tetraploid species. It is difficult to see how H. falconeri, with its current distribution, could be a parent particularly of H. transsilvanica. Populations can, of course, expand and contract but the much smaller genome size may mean that it does not hybridise with other hepaticas. However, John Massey reports that seedlings have been raised from a cross between H. falconeri and H. americana, supporting the argument for retaining the species in Hepatica. H. falconeri in many ways resembles several Anemone species in habit and morphology including A. flaccida. Ogisu, Mabuchi and Mikanagi (2002) retain H. falconeri in Hepatica due to the 272
Hepatica falconeri at Ashwood
shape of its involucre bracts, pistils and achenes, which more closely resemble Hepatica than the morphologically similar A. flaccida. H. falconeri also produces flowers before the new leaves, a characteristic of other Hepatica species. In addition, the chromosome number and organisation of the chromosomes has a strong affinity with H. japonica. Further work is required to show definitively the identity of this species. It will be interesting to see if H. falconeri crosses with other hepaticas produce viable progeny and whether these plants show characteristics similar to the proposed allotetraploids – H. henryi, H. transsilvanica and H. yamatutai. THE ALPINE GARDENER
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The flowers of Hepatica falconeri, which is new to cultivation in the UK
Hepatica henryi
A diminutive Chinese species that is confined to the municipality of Chongqing and the province of Hubei, found at 1,400-1,800m. H. henryi is most commonly seen with white flowers but pale pink and blue are also known. The leaves are three lobed and scalloped, the young leaves often bronze-tinged and becoming greener with age. The reverse of the leaf is generally flushed purple. Several attractive double-flowered clones have appeared in recent years. Said to originate from a single site, they were introduced by Kaichen Nursery and will no doubt be highly sought after SEPTEMBER 2015
Hepatica henryi leaves
by collectors. John Massey has found that H. henryi also crosses with H. nobilis to produce hybrids that are larger and more vigorous. 273
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Hepatica henryi exhibited at the Cleveland AGS Show in April 2010 and, right, a double form of H. henryi
Hepatica insularis
This Korean endemic may be included with H. asiatica, with which it has a close affinity. It is distinct in having smaller leaves with two (or more) prominent pale markings. The flowers are very similar to H. asiatica and, like this species, are usually white. Double and coloured forms are known to exist but are rare. H. insularis grows in the extreme south of South Korea as well as several offshore islands including Cheju Do, where it was seen growing on Mount Halla by John Massey. H. insularis often has very attractive foliage. The new, bronze-tinged leaves 274
are produced at flowering time and so contrast nicely with the flowers, in some forms the paler markings extending over much of the leaf.
Hepatica japonica
H. japonica is a widespread and variable species in Japan and several THE ALPINE GARDENER
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Hepatica insularis flowers are usually white, though coloured forms are known to exist. Below left, its typical leaf markings and, right, a marbled leaf
distinct forms have been recognised. In Japan, where it is commonly called Yukiwariso, it has been cultivated as an exhibition plant since 1603 but has seen a huge resurgence of interest in the last 40 years. Since it is highly variable in the wild, distinct forms were collected by enthusiasts and until recently most SEPTEMBER 2015
Japanese Hepatica cultivars were wildcollected variants. It is only in the last 30 to 40 years that some enthusiasts such as Kouichi Iwafuchi and Mr Tomizawa have started breeding new varieties. H. japonica f. japonica is a small plant with acutely lobed leaves. The flowers are mostly white with 9-20 slender 275
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Hepatica japonica ‘Ryoku Un’, one of hundreds of named cultivars
sepals. H. japonica f. japonica establishes smaller populations than the other forms, growing on mountains at 300950m along the south-west and southeast coast of Honshu, Shikoku and northern Kyushu. Most of the named variants are derived from H. japonica f. magna, which has wide variation in the wild. Typically it may have 6-13 oval sepals in a wide range of colours, including yellows and greens and double forms. The yellow cultivars require careful cultivation since they fade in strong light. The leaves typically have rounded lobes although they may occasionally be more pointed. H. japonica f. magna is found in the north-west of Honshu from sea level to 500m, often on steep slopes. H. japonica f. variegata has typically 276
6-10 oval sepals and is predominantly white, although pink and red forms are known. The leaf lobes are rounded. H. japonica f. variegata grows in the northwest of Honshu at altitudes of 150-770m. John Massey reports seeing it growing among bamboo next to paddy fields. H. japonica is a very variable plant producing the most sensational and unusual flowers in the genus, with hundreds of named cultivars. Some varieties are said to be scented, but this could be a reference to forms of H. pubescens and requires confirmation. On Facebook, photos have recently been posted of plants with yellow, variegated and bright purple leaves but it is unclear if these characteristics are stable or the result of disease or nutrient deficiency. The International Hepatica Society THE ALPINE GARDENER
HEPATICAS
Hepatica japonica ‘Hatsune’
(IHS) and Japanese Hepatica Society recognise nine groups based on the morphology of the flowers: Hyoujunka (single-flowered). Otome-zaki (single flowers without stamens but with pistils). Nidan-zaki (straight, flat, coloured, petaloid stamens, pistils normal). Nichirin-zaki (stamens are short, green, usually infertile and petaloid, pistils normal). Chyouji-zaki (as above but twisted petaloid stamens). Karako-zaki (as above but layers of petaloids covering the gynoecium). Sandan-zaki (the stamens and pistils are infertile and usually green and petaloid; young and newly divided plants may have fertile anthers that can be used for breeding). SEPTEMBER 2015
Senju-zaki or Senne-zaki (commonly called the thousand-layered flower, these are fully double). Yousei-zaki (a layer wreath of straight petaloid stamens; most pistils are petaloid). Hepaticas are displayed in Japan in a similar manner to the way that Primula auricula cultivars are shown in the UK. Key shows take place in Niigata and Tokyo, where plants can exchange hands for thousands of pounds. Plants are shown in individual pots that are porous, have a large drainage hole and stand on small feet. Wire frames help keep the leaves off the pots. Growers take off their shoes and put on slippers to walk around the displays. A variety of novel substrates is used by Japanese growers. The cultivation 277
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Hepatica japonica ‘Hohobeni’ (atypical)
Hepatica japonica ‘Tiono Koto Buki’
Hepatica japonica ‘Tama Hime’
Hepatica japonica cultivar
Hepatica japonica ‘Sou-Shun-Ka’
Hepatica japonica ‘Yahiko’
of hepaticas in Japan was described in detail by Gunther Kleinhans in The Alpine Gardener in 2005 (volume 73, pages 330-342).
There is currently an application to establish a National Collection of Japanese cultivars from Andy Byfield in Devon.
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HEPATICAS
Hepatica japonica ‘Tamamushi’
Hepatica japonica ‘Anjyu’
Hepatica japonica ‘Sansetsu’
Hepatica japonica ‘Shikouden’
Hepatica japonica ‘Yume Ji’
Hepatica japonica ‘Haruno-Away-Uki’
Hepatica maxima
often under rhododendrons. It is the largest species with white, occasionally pink-tinged flowers that surmount a large involucre. The trilobate, evergreen
H. maxima is an endemic of the island of Ullung-Do, situated off the east coast of South Korea. It grows in dense shade, SEPTEMBER 2015
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Hepatica maxima and, right, from top, three pictures showing its seed development
leaves are large and leathery with a finehaired margin. The older leaves develop a purple tinge on their undersides. H. maxima is sometimes a disappointing plant because the flowers can be small with narrow sepals. It does, however, have a number of distinctive features. The seeds take much longer to ripen than in other species, and are often not shed until August or September in 280
cultivation. They are contained within clusters of achenes which are still green when other Hepatica seed is ripe. Over the summer the top part of the seed starts to turn black and the base white, hence the nickname ‘panda seed’. As with other species, seed should be sown fresh but a high proportion takes two years to germinate. H. maxima has proved to be valuable THE ALPINE GARDENER
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Varied forms of Hepatica pubescens at Ashwood Nurseries
in hybridising and is one of the parents of H. x schlyteri. John Massey reports that the leaves of H. maxima become chlorotic when not fed and that the largest leaves are produced when the plant is grown in deep shade.
Hepatica pubescens
H. pubescens is often treated as a variant of H. japonica. In the wild it grows in the central mountains of Honshu at altitudes of 100-1,260m. John Massey reports that plants around Osaka in the Rokko Mountains and those in Okayama Prefecture generally have dark pistils and a smaller number of stamens SEPTEMBER 2015
Hepatica pubescens leaves
and sepals than H. japonica. The newly emerged leaves are generally dull due to a covering of fine hairs. These are typical characteristics of plants in cultivation, which are frequently bicoloured or picotee. The picotee forms with darker 281
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The picotee flower of Hepatica pubescens ‘Tenjin-Ume’ Below, a Hepatica pubescens hybrid. Blueflowered forms of the species are unknown
pistils are exceptionally attractive and have led to numerous named selections such as ‘Tenjin-Ume’. H. pubescens is a tetraploid species. However, one of the best known cultivars, ‘Tenjinbai’, has been shown by Ben Zonneveld to be a pentaploid. ‘Tenjinbai’ has attractive pink flowers with a picotee edge and darker pistils. The leaves are dull and slightly marbled. I was shown this cultivar by Marlene Ahlburg and detected a delicate scent from the flowers. This does not seem to be consistent, but seed-raised plants are almost certainly passed around under this cultivar name. H. pubescens ‘Tenjinbai’ was used by Marlene Ahlburg to create the first H. x euroasiatica hybrids in an attempt to create garden-worthy plants with picotee-edged flowers. John Massey reports that blue-flowered 282
forms of H. pubescens are unknown and that any such plants in cultivation are likely to be hybrids.
Hepatica yamatutai
H. yamatutai is a Chinese species that has a very restricted distribution in the wild. It is found only on Mount Emei in Sichuan at 1,100-2,100m. The species is occasionally referred to as H. THE ALPINE GARDENER
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The pentaploid cultivar Hepatica pubescens ‘Tenjinbai’ Below, Hepatica yamatutai flower and leaves
henryi var. yamatutai, but recent work by Ben Zonneveld suggests otherwise. The five-lobed leaves are acutely lobed, not rounded and three-lobed as in H. henryi, but like this species often have a purple-tinge to the reverse. The leaves are often attractively patterned with darker or silvery markings. The large, usually white flowers are occasionally tinged pink on the reverse. SEPTEMBER 2015
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A semidouble and, below, double forms of Hepatica yamatutai
Recently a number of double and semidouble forms have been imported from China, and these promise to be highly collectable. John Massey also reports that there are double forms with dark pink reverses to the sepals. H. yamatutai is a highly attractive plant when grown well. The foliage can provide added interest and in hybrids with H. nobilis the progeny often have good ‘variegated’ leaves.
Interspecific hybrids Hepatica x euroasiatica
H. x euroasiatica is the artificial hybrid designation suggested for H. transsilvanica x H. pubescens. If accepted, it strictly speaking cannot be used for crosses using H. japonica. The name has 284
been used in several publications but I cannot find a valid description. The first crosses using these parents were probably by Marlene Ahlburg in the early 1990s. On visiting her garden in Rötgesbüttel in 1997 I was shown a copy of my 1990 article in The Alpine Gardener with the THE ALPINE GARDENER
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Hepatica x euroasiatica ‘Rötgesbütteler Röschen’ in Marlene Ahlburg’s garden
following words underlined: ‘I think the more exciting possibilities would be through hybridisation, in particular by crossing the various colour forms of H. nobilis var. japonica [now H. japonica] and H. transsilvanica...’ I was then shown three flowering hybrids: ‘Rötgesbütteler Röschen’ with delicate, pink picotee flowers; ‘Max Leichtlin’ with pale blue flowers and marbled leaves; and ‘Prof. Friedrich Hildebrandt’ with blue, picotee flowers. All three plants had H. pubescens ‘Tenjinbai’ as the seed parent and H. transsilvanica as the pollen parent. Even at the seedling stage,the plants displayed intermediate leaves typical of H. x media so that the success of the cross could be confirmed even before flowering. SEPTEMBER 2015
Since these initial crosses, several more have been performed by other hybridisers and selections named. The use of H. transsilvanica as one parent should produce at least some seedlings with the hardiness and creeping habit of this species. H. pubescens (and H. japonica) provide a wide range of colour forms that offer the potential for exciting hybrids. When used as the seed parent, H. pubescens tends to produce far more seed than H. transsilvanica. Work by Ben Zonneveld has helped to confirm the parentage of ‘Rötgesbütteler Röschen’ and ‘Prof. Friedrich Hildebrandt’. However, two distinct acquisitions of ‘Prof. Friedrich Hildebrandt’ did show widely different genome sizes. 285
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Hepatica x media ‘Ballardii’ Below, Hepatica x media ‘Sue White’
Hepatica x media
Hepatica x media was first described by Lajos Simonkai in 1886 from natural hybrids between H. transsilvanica and H. nobilis found in Romania. The first record of artificial hybridisation is by Prof. Friedrich Hildebrandt in 1890. In about 1917, Ernest Ballard used selected forms of both parents to repeat the cross from which one seedling was selected and named ‘Trilosa’ (after H. nobilis syn. H. trilosa x H. transsilvanica syn. H. angulosa). At some point this plant was renamed ‘Ballardii’ and under this name it won the RHS Reginald Cory Memorial Cup in 1938. H. x media ‘Ballardii’ is intermediate between both parents with leaves resembling H. transsilvanica, though more leathery, and with large, rounded, powder-blue flowers. 286
Until recently there were no other known H. x media cultivars. On the Continent, several plants were suspected of being hybrids but many are likely to be H. transsilvanica. Ben Zonneveld has confirmed the identity of some cultivars by looking at genome size: hybrids will be triploids and therefore have a genome THE ALPINE GARDENER
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Hepatica x media ‘Kilmeston Beauty’, raised by Robin White
size halfway between both parents. Triploids are likely to be sterile and this is the case with ‘Ballardii’. In 1998 Severin Schlyter reported having raised a self-fertile hybrid using H. nobilis var. glabrata as the pollen parent. In the 1990s Robin White of Blackthorn Nursery raised seedlings from a pink form of H. nobilis that had been pollinated by a blue H. transsilvanica. Of the resulting seedlings one was named after the raiser’s wife. Hepatica x media ‘Sue White’ is pale pink and sterile. A similar seedling from the same breeder is ‘Kilmeston Beauty’, said to be more vigorous. This cross offers breeders one of the best opportunities to create garden-worthy, hardy hepaticas. Several breeders such as SEPTEMBER 2015
John Mercer have raised new seedlings in a range of colours and hopefully the best will come into cultivation.
Hepatica x schlyteri
This hybrid commemorates Severin Schlyter, who may have been the first breeder to hybridise H. nobilis and H. maxima. Schlyter’s original blueflowered plant was named ‘Nomax’ (after the parents). Fred Bundy also raised a blue-flowered seedling named ‘Frances’ in May 1996 using H. maxima as the seed parent. John Mercer has raised blue and red flowered seedlings which were not named. The best known H. x schlyteri hybrids are those raised by Robin White. H. x schlyteri ‘Blue Max’ was raised from H. maxima and a dark 287
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The flowers of Hepatica x schlyteri ‘Blue Max’ and ‘Red Max’. Below, the white flowers of H. x schlyteri ‘The Bride’, all raised by Robin White
blue H. nobilis in 1997. The first flowers were borne in 2000 and ‘Blue Max’ was selected. It is a stout plant with dark blue flowers. Robin White reports that this and several other H. x schlyteri hybrids are grown outside in a woodland bed composed of alkaline clay, enriched with potting compost. A deep pink seedling called ‘Red Max’ was also raised at Blackthorn along with the white-flowered ‘The Bride’. All three plants have flowers that are much larger than H. maxima while the leaves tend more towards H. maxima. H. x schlyteri ‘The Bride’ is unusual in that it is fertile. Most seedlings will resemble the seed parent, but John Massey reports that ‘The Bride’ will also cross with H. transsilvanica to create some potentially interesting threespecies hybrids. At Ashwood Nurseries, a range of H. 288
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Hepatica x schlyteri (H. maxima x H. nobilis ‘Cremar’) from John Massey Below, Hepatica x schlyteri (H. maxima x H. nobilis var. pyrenaica) and its leaf
x schlyteri Ashwood Hybrids has been raised using different parents. Plants are available in the usual pink and blue forms but by using H. nobilis ‘Cremar’ John Massey has produced some exciting foliage forms. The deep pink form illustrated has the added interest of scalloped and marbled leaves. My plant from this cross is fertile. Attractive bicolours and appleblossom pink forms with marbled leaves have resulted from the use of H. nobilis var. pyrenaica.
Hybrids without a recognised binomial
John Massey reports that H. acutiloba x H. nobilis hybrids are sterile and have a long flowering period. They can also be fragrant. The plants seen at Ashwood look as if they would appeal to alpine enthusiasts who grow for showing. SEPTEMBER 2015
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Hepatica acutiloba x H.nobilis ‘Cremar’ Below, H. acutiloba x H. transsilvanica
There is clearly great potential for influencing the characteristics of the progeny through carefully selecting the parent plants. Scent, for example, is more likely to be passed on if a scented H. acutiloba parent is used. Interesting leaf characteristics can be manipulated using parents such as H. nobilis ‘Cremar’. Two seedlings seen at Ashwood also had attractive flowers (one is pictured on the cover of this issue of The Alpine Gardener and the other is shown above). H. acutiloba has also been crossed with H. transsilvanica to producing seedlings with extra sepals and few, if any, stamens. Hybrids between the American and European species are not new. In 1989 Kath Dryden described a plant sent to her from H. Lincoln Foster in Connecticut some years previously that 290
had occurred as a spontaneous seedling. H. ‘Millstream Merlin’ is allegedly a hybrid between H. americana and H. transsilvanica, but John Massey has suggested that H. acutiloba is a possible parent since Ashwood hybrids of this parentage can resemble ‘Millstream Merlin’. H. ‘Millstream Merlin’ was THE ALPINE GARDENER
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Hepatica americana x H. transsilvanica (or is it?) ‘Millstream Merlin’
originally described as a form of H. x media in 1989 when it received an Award of Merit. The semi-double flowers are deep purple in bud but fade as they age. The leaves are similar to H. x media but more acutely lobed. John Massey also refers to H. ‘Millstream Pink’ but I have not seen this plant and it has been cited elsewhere as a form of H. acutiloba. ‘Millstream Merlin’ is now well established in cultivation and popular among enthusiasts partly because of its long flowering period, no doubt due to its sterility. H. henryi x H. nobilis seedlings grown by Ashwood Nurseries are intermediate between the parents. The leaves especially share characteristics from both. SEPTEMBER 2015
Hepatica maxima x H. pubescens
John Massey reports that some seedlings of H. maxima x H. acutiloba can be fragrant. H. maxima x H. pubescens seedlings have exceptionally attractive flowers. The plant illustrated has a paler centre giving an extreme picotee effect. 291
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Hepatica nobilis x H. acutiloba ‘Hazelwood Froggie’ and its marbled leaf. Below, H. nobilis crossed with H. acutiloba at Ashwood
H. nobilis x H. acutiloba has produced, as previously mentioned, some excellent plants. One notable cultivar raised by National Collection holder Glenn Shapiro is ‘Hazelwood Froggie’. This plant occurred as a spontaneous seedling next to a plant of H. nobilis var. pyrenaica ‘Apple Blossom’. The pollen parent is assumed to be H. acutiloba since the leaves are acutely lobed but marbled as seen in ‘Apple Blossom’ and the pale blue flowers are held on upright stems. The flowers are sterile. Ashwood Nurseries has also 292
raised H. nobilis x H. acutiloba seedlings that also have apparently sterile flowers and marbled leaves. Crosses between H. nobilis and H. japonica have the potential for creating a wide range of colours in the resulting seedlings, and line breeding could potentially create stable colour strains. The first crosses that I was aware of were carried out by John Mercer in 1996. A range of colours including a deep pink were produced and the plants have proved hardy and long-lived. Gunhild Poulsen in Denmark has also raised THE ALPINE GARDENER
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Hepatica transsilvanica x H. yamatutai
some lovely hybrids that she refers to as H. x eurasia. The cross H. pubescens x H. yamatutai has the potential for interesting plants since both parents are tetraploid. The H. pubescens parents have potentially some of the most attractive flowers while some forms of H. yamatutai have arguably the best foliage in the genus. Some of the first crosses at Ashwood have picotee flowers and heavily marbled foliage demonstrating the potential for this combination. H. yamatutai has also been crossed with H. transsilvanica at Ashwood to produce flowers with very rounded sepals. When H. yamatutai is crossed with H. nobilis, seedlings can have good variegated foliage in addition to large flowers in a range of pastel shades. SEPTEMBER 2015
Hepatica pubescens x H. yamatutai
This cross has also been made by Robin White. At the Loughborough AGS show in March 2014 a mid blue-flowered plant of H. japonica x H. yamatutai won a Certificate of Merit for Rosina Abbiss. Other known hybrids include H. americana x H. japonica. 293
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A white outcome from crossing Hepatica yamatutai and H. nobilis. The cross also produces flowers in a range of pastel shades
Jürgen Peters’ catalogue lists a range of Hepatica hybrids under the names H. x trans-acut, H. trans-japonica, H. x petersii, H. trans-crenata and H. x harvingtonii, but none of these names have been validly published to my knowledge and the latter two would be invalid as they do not refer to interspecific crosses.
Conclusions I have attempted to highlight the problems of nomenclature in the genus Hepatica. As stated in the introduction, plant taxonomy is in many ways a subjective science, and modern techniques such as investigating nuclear DNA content should improve our understanding of the different species. These findings may have important implications for how the genus is viewed. Individual, superficial morphological 294
characteristics are generally not good indicators of speciation. However, when other features, geographic isolation and genetic factors are taken into account, the genus could be viewed as follows: Hepatica nobilis Schreber var. glabrata Fries var. pyrenaica Hepatica transsilvanica Fuss Hepatica americana subsp. americana (DC.) Ker Gawl. Hepatica americana subsp. acuta (Pursh) Zonn. Hepatica asiatica Nakai subsp. asiatica Hepatica asiatica subsp. insularis (Nakai) Zonn. Hepatica maxima (Nakai) Nakai Hepatica henryi (Oliv.) Steward Hepatica yamatutai Nakai THE ALPINE GARDENER
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Features of Hepatica species to consider for breeding H. nobilis
Hardy and easy to grow in the UK climate. Good seed parent.
H. nobilis var. pyrenaica
As above. Pastel shades and marbled leaves.
H. transsilvanica
Hardy and easy to grow in the UK climate. Creeping habit.
H. americana subsp. acuta Upright flowers. Can be scented. H. asiatica subsp. insularis Some have attractive leaves. H. maxima
Hybrids are stout, floriferous plants with large leaves. Hybrids occasionally fertile.
H. henryi
Some have attractive leaves.
H. yamatutai
Some have attractive leaves.
H. japonica f. magna
Wide range of colours.
H. pubescens
Wide range of colours. Some picotee, some scented.
Hepatica japonica f. japonica f. magna f. variegata Hepatica japonica var. pubescens Hepatica (Anemone) falconeri (Thomson) Steward The elevation or demotion of different species would affect our view of hybrids and any current or proposed designations. Many hybrids currently cultivated seem to be lumped into H. x media. Clearly the validity of this depends on the status of the parent plants. H. nobilis var. pyrenaica does not appear to have been validly published as a botanical variant while, more importantly, no author is obvious for the SEPTEMBER 2015
now widely accepted H. japonica, which in most botanical papers is still given under H. nobilis or more recently as a subspecies of H. asiatica. Most of the species have now been crossed to create some attractive and potentially garden-worthy plants. Breeders should pay attention not only to the species used in breeding but also the ‘quality’ of the parent plants. Some crosses are known to produce sterile offspring (especially those between diploid and tetraploid parents), and these may have the advantage of a longer flowering period while fertile offspring offer the opportunity of back-crosses or the introduction of further species to produce complex hybrids. Most breeding so far has been quite haphazard so it will be interesting to 295
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Hepatica japonica ‘Ryo Kusetsu’
see what can be achieved with a more focused breeding programme. The best characteristics of different species must be recognised and selected in order to breed plants with those desirable characteristics. It would be interesting to cross H. falconeri with H. asiatica and H. nobilis to see if any seedlings resemble the allotetraploid species. John Massey states that Ashwood does not name any plants that cannot be commercially propagated, a stance that I would support. Breeding programmes should concentrate on strains (cultivars) that share common characters and can be raised from seed, or cultivars that can be vegetatively propagated. Hepatica breeding has come a long way in the past two decades due to the 296
availability of new species and cultivars. This is likely to continue as the genus becomes better known. In Japan hepaticas have a cult following and while this has not been realised in the UK there is no reason why these colourful plants should not continue to increase in popularity. The European species are readily cultivated in UK gardens provided a few basic rules are followed (see the following article on cultivation) while new hybrids may increase further the range of plants that can be grown outside. The American and Asiatic species are likely to remain more challenging but the growing range of colours and forms that are becoming available can only increase their appeal to alpine growers and other enthusiasts. THE ALPINE GARDENER
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Insulated troughs protect the plants in Anne Wright’s winter Hepatica house
T
he cultivation of hepaticas among enthusiasts at first seems extremely diverse since a range of methods and housing are adopted. Each technique, however, obeys several fundamental rules which in turn are determined by the natural habitat and growth cycle of each species. Most hepaticas are woodland herbs that flower before the leaf cover from deciduous trees creates dense shade. They are relatively dry in winter if covered by snow, and dry in summer due to the leaf canopy above. In autumn they are mulched by falling leaves and kept moist by rain. In spring there is plentiful moisture due to snowmelt and rain. As a consequence hepaticas benefit from good light and plenty of moisture
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How to grow hepaticas while flowering, but as the flowers fade and new leaves emerge they should be shaded to mimic the emerging canopy of leaves on deciduous trees. Watering (and feeding) may be reduced in summer before increasing both of these in autumn and removing any shading. The European hepaticas are cultivated outside by many growers, but only a few succeed with the American and Asiatic species. As a consequence these are normally grown in frames or glasshouses so that conditions can be controlled. Some growers transfer their plants 297
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Anne Wright’s summer Hepatica house with netting to provide shade
from sunnier conditions in the autumnspring period to a shadier site in the spring (after flowering) until the autumn. Anne Wright grows her plants in an alpine house lined with bubble wrap in winter, with the pots kept in insulated troughs to protect from excessive frost. Container-grown plants, especially the Asiatic species, do seem susceptible to excessively cold winter temperatures but this may have more to do with fluctuating temperatures than freezing alone. In summer Anne transfers her plants onto benches in a net-lined structure that gives about 50 per cent shading. This structure provides good air flow as well as shade, keeping the plants cool and reducing the build-up of pests and diseases. I adopt a similar strategy with 298
plants grown in a traditional alpine house from autumn to spring and transferred to a shady netted frame in summer. The National Collection holder, Glenn Shapiro, grows her hepaticas on tables in a converted barn with additional shading and uses both plastic and clay pots. At Wisley a traditional wooden alpine house has been converted for the Hepatica collection. The plants are grown in clay pots on mesh benches with additional ventilation provided by fans. About 70 per cent shading is applied over the period of British Summer Time using a mixture of Coolglass, external shade netting and additional shading stretched over plastic hoops positioned above the plants. The Hepatica house at Ashwood (pictured on page 253) THE ALPINE GARDENER
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Glenn Shapiro’s National Collection is kept on tables in a converted barn
is similar with excellent ventilation provided by side and roof vents and fans. The plants are grown in clay pots on slatted benches. Internal 75 per cent shading is applied after flowering until mid-winter. Temperatures are not allowed to fall much below freezing in winter. At Ashwood and Wisley the plants are spaced well apart and grown on slatted benches to aid drainage, assist air circulation and reduce the potential transfer of root nematodes between plants. Edrom Nurseries provide their plants with far less pampering. Owners Terry Hunt and Cath Davis grow their Japanese cultivars on low benches in crates. Almost all the plants are grown in 9cm square plastic pots. Most are imported as single crowns and grown SEPTEMBER 2015
on for two to three years before sale. Japanese cultivars have also been grown outside in the woodland garden at Edrom for the past 5-6 years, surviving temperatures as low as -20C. The woodland is a mixture of coniferous and some deciduous trees. Robin White grows a range of H. nobilis, H. transsilvanica, H. x media and H. x schlyteri outside in a woodland bed. The soil is heavy alkaline clay enriched with old potting compost. The improvement of garden soil with organic matter and the use of shade are common factors among those who grow hepaticas outside. The pH of the soil seems to be less important than an open, well-drained soil. European hepaticas can thrive on enriched, alkaline soils, an ericaceous peat bed and well-drained 299
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At Edrom Nurseries hepaticas are grown in 9cm pots in plastic trays 300
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Jürgen and Timo Peters in one of their shade tunnels
sandy soils. John Massey reports that Hugh Nunn of Harvington Nurseries top-dresses plants with fish, blood and bone in late winter while at Ashwood calcified seaweed is used. Caution is required when using bulky manures: I recall large beds of H. transsilvanica at the Royal Botanic Garden Edinburgh killed through over-application of farmyard manure. When I visited Jürgen Peters in northern Germany in 1993, he was growing many of his stock plants in deep organic beds in shade tunnels that mimic woodland conditions. This offers a manageable solution where many plants are required for stock.
Growing media
A few simple rules apply to potting composts. They must be moisture SEPTEMBER 2015
retentive but open and well drained, and must not be over-compacted. The most popular mix is based on one part 2-5mm horticultural perlite, one part sifted leafmould (or composted bark) and one part John Innes No. 2 or 3. At Wisley a very coarse perlite is used. Perlite has found increased favour in recent years over horticultural grit. Slow-release fertiliser is added such as 12-month Osmocote at 1g per litre or TEV 04 (Vitax Q4) at 3g per litre. At Wisley the standard mix also includes 3g of dolomitic limestone (Dolodust) per litre of compost. At Ashwood the amount of dolomitic limestone is doubled for the Chinese species. John Massey top-dresses plants with fine bark to stop the perlite from coming to the top of the pot but acknowledges that this may encourage Botrytis. 301
PRACTICAL GARDENING Watering is carried out in the morning around the edge of the pot to reduce the risk of fungal diseases. Most growers provide additional fertiliser for their plants through the growing season, although opinions differ somewhat. At Ashwood plants are fed with Maxicrop in spring and autumn, but never in summer when they are less active. Glenn Shapiro uses a halfstrength dose of Tomorite with every third watering. At Edrom plants are fed after the new leaves have hardened up through until autumn. If plants are newly divided they are not given any additional feed until established. At Wisley no additional feed is provided apart from a fortnightly ‘compost tea’ via a Dosatron device. Plants should be well watered during spring. At Wisley watering is carried out once a week from autumn to spring and plants are never allowed to dry out. In summer watering is more liberal with the glasshouse damped down to increase humidity. Other growers keep hepaticas drier in summer but do not allow them to dry out at any time.
Massey, this provides protection for the emerging flowers. At Wisley the old leaves are removed as soon as the new ones start to emerge. If plants are grown for exhibition the removal of old leaves can create a more pleasing display.
Plant husbandry
Hepaticas do not suffer greatly from pests and diseases but a number of problems require vigilance. Botrytis (grey mould) can attack buds and leaves, especially if plants are kept too damp. When removing old leaves try to avoid leaving stalks that can rot. Old flowers, especially doubles, can also act as an entry point for the fungus. Mice and slugs can attack dormant buds in winter and emerging buds in early spring, so preventative measures should be taken where possible. Pot-
Growers disagree about removing the old leaves of hepaticas. If grown in pots the old leaves can look unsightly and hide the flowers and emerging new leaves. Removing the old leaves prior to flowering allows the flowers to be displayed more effectively. I favour removing the old leaves as the flower buds start to emerge. Robin White removes the central leaves in February leaving those around the perimeter. According to John 302
Repotting
Hepaticas should not be over-potted and so may not need repotting every year. Repotting also offers the opportunity to divide plants. Most growers agree that plants should be repotted either immediately after flowering or preferably in early autumn. Of the growers I have consulted, only Gunhild Poulsen repots throughout the year and divides plants in July, and it may be that the climate in Denmark supports this technique. John Massey routinely removes compost from the roots and removes damaged and diseased roots when repotting. It is essential not to over-compact the compost. H. transsilvanica has a reputation for being shy-flowering and anecdotal evidence suggests that it flowers better when pot-bound.
Pests and diseases
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Above left, old leaves on Hepatica transsilvanica are removed in late February to reveal the emerging flower buds, left. Just two weeks later, above, the flowers are well displayed and new leaves are beginning to grow at the base
grown plants are more easily protected. Nematodes can attack roots, where they form nodules. Since there are few viable treatments, affected plants should be isolated and roots trimmed back when repotting, or destroyed. Plants grown in sand plunges may be more vulnerable to nematodes. Viruses are also difficult to treat and difficult to identify. Plants suspected SEPTEMBER 2015
of being virused, showing irregular chlorosis or distorted leaves, should be isolated from healthy plants and destroyed if diseased. Aphids can be a problem, especially under cover, and can be vectors for the spread of viruses.
Propagation: seed
The ‘seeds’ of most Hepatica species in cultivation are shed in May and 303
PRACTICAL GARDENING if seed is sown as soon as it is ripe, germination is generally good. The ‘seeds’ are in fact single-seeded fruits called achenes, which are held in clusters until dehiscence (splitting). The fruits are derived from the carpels which in Hepatica have only a single ovule. It has been shown that at dehiscence the seeds have an immature embryo, which almost certainly explains the loss of viability if they are allowed to dry out. In the wild seeds are dispersed by ants, which are attracted to a sticky elaiosome at one end of the achene. Hepatica seed will quickly shed as it ripens and so some growers collect the seed in small bags. Marlene Ahlburg would encase the whole plant in a bag to ensure all seed could be collected. One study has suggested that H. japonica in the wild can take up to ten years to flower from seed, but in cultivation most species will germinate the following spring and flower in their third year. At Ashwood Nurseries, fresh seed is sown into a low-nutrient Hepatica compost and covered with a thin layer of grit. Seeds are kept cool and moist but not too wet. Andreas Händel uses a half pot of compost covered with gritsand before sowing the seeds, which are covered with a second layer of sand. Germination requires a period of cold, so seeds sown in May will generally germinate the following spring. The exceptions are Hepatica maxima and H. x schlyteri, which may take two years to germinate. It is not clear whether the seed parent used affects germination times. Of the growers I have consulted, only 304
Robin White pricks out seedlings at the cotyledon stage into modules. Most prefer to leave them until the following spring, allowing them to develop a more fibrous root system. If this is the case, it is beneficial to sow thinly. Often there is variation among the seedlings but some hepaticas seem to produce a high proportion of seedlings that are identical to the parents. H. nobilis and the other diploid species generally make better seed parents than the tetraploid species. If seedlings are the result of crosses, the use of certain seed parents can allow hybrids to be identified at an early stage since diploid species crossed with most tetraploid species will have more ornate leaves. It is not as easy to identify hybrids when tetraploid species are used as the seed parent. The female parts of hepatica flowers (stigmas) become receptive before the male parts, the stigmas glistening when ripe. The male stamens do not shed pollen until the point at which the flowers are going over. Some growers remove the sepals and stamens when crossing onto the seed parent.
Propagation: division
Dividing established plants offers a way of increasing cultivars. John Massey prefers to divide plants in the autumn when they seem to establish better while at Edrom plants are split after flowering. Most growers remove the old compost and trim the roots (reduce by at least a third) when repotting, which seems to stimulate re-establishment and allows for the removal of any root nodules. It is essential not to compact the potting THE ALPINE GARDENER
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A cluster of achenes close to dehiscence on Hepatica nobilis
media: any firming should be very light such as tapping the pot on the bench. The crown of the plant should be positioned at the compost surface. It has been reported that some hepaticas, including double forms of H. henryi, have been propagated by root cuttings. Certainly roots with dormant shoots do offer a viable if slow method of propagation. The basic principles of cultivation can be summarised as:
Keep fairly dry in winter. Water well and provide good light in spring/autumn. Feed while in active growth. Shade heavily (50-70 per cent) and keep drier in summer. Remove shading in autumn and water well. Be vigilant for Botrytis, virus and root nematodes. Be vigilant for slugs and mice attacking buds.
Acknowledgments: Michael Myers wishes to thank the following people for their co-operation in the preparation of his articles on hepaticas: Marlene Ahlburg, Fred Bundy, Diane Clement, Ray Cobb, Colin Crosbie (RHS Garden Wisley), Terry Hunt and Cath Davis (Edrom Nurseries), Andreas Händel, Dr Tomoo Mabuchi, John Massey (Ashwood Nurseries), John Mercer, Jürgen Peters, Gunhild Poulsen, Lucie Rudnicka (RHS Garden Wisley), Glenn Shapiro (National Collection holder), Robin White, Anne Wright, Bleddyn and Sue Wynn-Jones (Crûg Farm Plants). SEPTEMBER 2015
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HOW TO GROW IT Acanthus hirsutus subsp. syriacus
I
n high summer, while the herbaceous border is at full throttle, the rock garden is all too often an unexciting affair, lacking in variety and surprise. What to do? Well, there are numerous relatively dwarf plants that aren’t seen at their best in bedding schemes and cry out for repositioning against stone or gravel. If sensibly deployed, where they won’t overwhelm their near neighbours either in scale or by encroachment, several of the hardy Acanthus fit the bill. Journeying in Turkey south-east of Izmir last spring, I encountered two species, A. hirsutus and A. spinosus, colonising railway tracksides, stony field margins, rock-strewn slopes and even pushing up through the bases of old walls. They were not in flower so early in the year, but their ornamental leaves were attractive in their own right. Long ago they were notably sculpted as motifs on Corinthian columns. Their contemporary decorative use as living plants is now in its ascendancy, given their drought tolerance, longevity, a protracted flowering period, ornamental seed heads, fragrance (a few species) and overall impact. A. mollis was introduced to British gardens in the mid-16th century, followed by A. spinosus 70 years later, and there have been numerous later importations. The stridently bicoloured and many-flowered spikes thrust skywards from late May or June through to August. Ignore tenderlings from tropical Asia
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Turkish bears’ breeches By Robert Rolfe and Africa and focus instead on the reliably hardier contingent (five in all) from Turkey, some of which also spill westwards to Italy, and south-eastwards to Syria, the Lebanon, Iraq, Iran, and possibly even the Yemen. Long-lived, long-flowering and long known in gardens, they bring bravura to the rock garden at a time when it most needs an injection of theatre. Before then, their foliage – variously spiny, deeply incised, deep green or rarely rich yellow-suffused as with A. mollis ‘Hollards’s Gold’ – is striking in its own right. Luxuriant clumps bring an air of sophisticated exuberance to any well-drained site or even a deep container. Clumsy handling at the seedling stage is probably the main cause of failure ‒ the thickening roots are vulnerable if broken off early in life, whereas mature plants can be readily propagated by taking root cuttings in late autumn or winter, an operation that clearly involves deliberately inflicted damage. The seeds are large enough to sow singly, in pots of decent depth, the seedlings left undisturbed until their second or even third year before planting out. Soggy soil is their other great hate. A THE ALPINE GARDENER
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Acanthus hirsutus subsp. syriacus enlivens the rock garden in late summer
slightly elevated site in sun or light shade and a gravelly loam of good depth afford near-perfect conditions. The introduction I particularly admire is Jim and Jenny Archibald’s mid1980s J&JA 106.500, from the Amanus Mountains above Hasanbeyli at 1,100m, where it was found occupying ‘open stony areas on west-facing slopes’. Identified provisionally as A. dioscoridis var. peringii, it has since been reassigned to A. hirsutus subsp. syriacus. It has established well from England’s south coast northwards to Scotland, where the plants shown were photographed, in mid-July, without any overhead protection, flowering at a height of around 45-50cm. This is the upper end of its height range (dwarfer variants get to only 20cm), and it is typically a plant of rocky limestone SEPTEMBER 2015
slopes and field margins, from 5001,900m, not just in southern and southeastern Turkey, but also, as the name specifies, western Syria. The leaves emerge quite late in spring, often not before May. In really dry conditions the plants will sometimes aestivate, or else develop mildew, in which case cut away the affected foliage, water well, and expect an unaffected replacement crop within a few weeks. Some species are stoloniferous, but not this one, which sends down deep, fleshy roots, and takes summer drought and winter cold in its stride. A wellestablished clump in full display can greatly enliven an otherwise somnolent, dryish area of the rock garden, perhaps in association with the airy, nodding heads of dieramas or a drifting surround of pinkish Diascia rigescens. 307
Cyclamen hederifolium, which begins to flower in late summer, is one of the harbingers of autumn
The allure of autumn
There is a wealth of plants to choose from to bring colour and interest to the garden in autumn. To celebrate the season, Robert Rolfe takes a romp through autumnal highlights in a variety of gardens. Then, on page 336, Peter Erskine selects three seasonal favourites and, on page 340, Robin White savours autumn crocuses
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Sternbergia lutea establishing well in AGS President David Haselgrove’s garden
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n September of last year, en route to London, my train reached West Byfleet, where a large sign proclaimed that this stop-off point for RHS Wisley was the ‘Home of West Hall Care Home’. Pretty uninviting (and tautologous) you might think, yet it stirred memories of a cheerier forerunner, displayed until the late 1990s at a station closer to my home: ‘Welcome to Loughborough, home of Ladybird Books’. A now defunct publisher, Wills & Hepworth, produced many titles under this imprint in the second half of the 20th century. One of these, What to look for in Autumn, is more evocative of that season than any other book I know.
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Part of a series covering all four seasons, its full-page illustrations by Charles Tunnicliffe RA portray bucolic scenes of dew-beaded cobwebs and the feathery plumes of travellers’ joy; starlings and wasps feasting on blackberries; shaggy ink-cap toadstools growing with meadow saffron in short grass; and skeins of geese flying in v-formation across a ‘cloud-dappled’ sky. Some like nothing more than a ‘good’ summer, by which they mean the warmer and sunnier the better. Others, me included, find such conditions energy-sapping, red spider mite-mired, hosepipe ban-threatening, and a trigger for that nowadays pandemic fad, the THE ALPINE GARDENER
JOHN RICHARDS
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Saxifraga fortunei at the Royal Botanic Garden Edinburgh
barbecue. Once June is through, this dog-day season endures two months too long. A distinguished succession of gardeners has also sought to expand the boundaries of autumn in order to have done with summer. Among them, E.A. Bowles considered a precocious Portuguese form of Colchicum (Merendera) montanum that appeared in early July ‘the first of all the autumnflowering bulbous plants to flower’. He was pushing it somewhat. Anthony Huxley, who gardened in Surbiton, only a ten-minute journey up the line from West Byfleet, was more realistic when he wrote a letter to The SEPTEMBER 2015
Garden in December 1992, recording a very early autumn brought about by what he dubbed a ‘queer year’, when Sternbergia lutea was in good flower by August 16. We illustrate it growing outdoors in our President’s new Wiltshire garden six weeks after that date, where it has settled down very well indeed. Observant gardeners in the British Isles know that the season is changing by mid-August when ornamental and berried seedheads start to appear, reaching a peak in October and November. I cannot explain why earlyfruiting plants as a general rule are, with notable exceptions, unexciting in 311
THE ALLURE OF AUTUMN seed, whereas those that come later are decorative and often palatable. Dispersal courtesy of consumption by wildlife clearly plays a part, as do structural mechanisms evolved to disperse seed at the optimum time for germination. Most of the photographs accompanying this article were taken between the second week of September and the last week of October. This is when the majority of autumn’s most notable flowering plants are at their best in the garden. I’m happy to acknowledge both earlier performers (Acis autumnalis is my default ‘here comes autumn’ indicator plant) and those that do well later, such as Saxifraga fortunei, spectacular outdoors in the absence of frost through to November. But the weather from one day to the next in late autumn especially can be capricious, with late performers such as Cyclamen cyprium and Crocus laevigatus often better under glass. Last November I visited Ray Cobb’s Nottinghamshire garden when the weather was behaving itself. Nearby, spectacular Elizabethan Wollaton Hall shimmered in the sunshine. Ray’s garden was abundantly strewn in both sun and shade with Galanthus reginae-olgae. He obtained stock long ago from onetime Surrey nurseryman G.B. Rawinsky, who had imported this in such quantity from Corfu that even after supplying the gardens at Buckingham Palace he was in a position to distribute the surplus. Iochroma australe, a Bolivian and northwest Argentinian Brugmansia relative with a long succession of blue flowers, somewhat fancifully compared to those of Gentiana acaulis but displayed upside down on a shrub to 5m tall, had its 312
Galanthus reginae-olgae
very last bloom still hanging on. With an altitude range of 2,200-2,600m, this exotic-looking, underused plant benefits from the protection of a wooden fence, wall or hedge and a well-drained soil. Several clones have been named since its reintroduction – the whitish ‘Andean Snow’ the most distinctive – thought to date from the 1960s. It is sometimes cut back hard in the winter or before it has had chance to shed its leaves. Ray, onetime holder of the National Collection of Crocus, has done a great deal to distribute material of so-called ‘heirloom’ pedigree and by doing so spread interest in this nowadays modish genus, whose species count has risen THE ALPINE GARDENER
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The underused South American Iochroma australe
dramatically, perplexingly almost on a monthly basis, in the last couple of years. It was from him that I received, almost 25 years ago, two corms of Spanish Crocus serotinus subsp. salzmannii f. albus ‘El Torcal’, which has increased clonally but never set a single seed with me. It needs a warm, dry summer and coldframe protection the year round, never failing to put on a tremendous display, when potted in late August and graded according to corm size, just three or four weeks later. Nearby grows Colchicum montanum, squatter and less needful of a ‘baking’. In most years they flower together, when the effect, if viewed with a fanciful eye, is that of massed applause SEPTEMBER 2015
from the pink contingent, whose corms in a good year will double or exceptionally triple, carried in stacked sequence within the old, brown, papery spent tunics. Other than those who have been to visit Ray, few will be aware of a superlative C. laevigatus selection, named in his honour, glistening white but with violetblue staining on the outer segments. Nor has the coining C. ‘Sylvia Cobb’ received much publicity. This in-effect albino version of C. pulchellus (the white anthers indicate as much) arose from a sowing of C. ‘Zephyr’ (in all likelihood C. speciosus x pulchellus) seed. A clonal name was decided after consultation 313
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Crocus serotinus subsp. salzmannii f. albus ‘El Torcal’ ‘applauded’ by Colchicum montanum
Crocus pulchellus ‘Albus’ 314
with the nurseryman and bulb expert Paul Christian. Then, a spanner in the works: a foreign nursery offered stock under this name, without reference to the dedicatee, and inevitably of differing origin. Meanwhile, C. pulchellus ‘Albus’ is at present readily available, the corms of remarkable size (commercially pumped-up on diluted cow manure, it has been suggested) and notably free with their flowers, up to eight apiece. Our photograph is of a dozen bought in mid-September and in full flower three weeks later. Just one corm produced lilac-blue flowers but was easily rogued THE ALPINE GARDENER
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A pair of wire-netting boxing hares in Rod and Jane Leeds’ Suffolk garden
and grown on separately, resulting in five slightly smaller ones when it was unearthed the following June. Coincidentally, in Suffolk, Rod and Jane Leeds have had similar results from C. ‘Zephyr’ sowings. Theirs is an all-year-round garden but one with an exceptional range of late-performing plants, very artistically juxtaposed. This same sensibility also informs the cleverly diverse and semi-informal layout of the garden, where you might come round one corner to find an ornamental hen house (with ceramic tiles made by Jane affixed to it), admire rich blue Codonopsis forrestii creatively entangled with pink and purple Rhodochiton SEPTEMBER 2015
atrosanguineus as they twine luxuriantly up a rustic pole, or look towards the field boundary and espy a larger than life but lifelike pair of boxing buck hares fashioned from wire netting. You should read Rod’s books Bulbs in Containers and especially Autumn Bulbs, for they distil many years of informed experience and are full of practical suggestions, a virtue lacking in some other books on bulbs. Rod, a former AGS President, and Jane make the point that at this time of year many winter-dormant plants have expanded their territories, covering ground colonised by autumn bulbs that are on the point of re-emerging. It is vital, therefore, that the bulbs are 315
THE ALLURE OF AUTUMN discreetly marked while in growth, and that a general tidy-up in early August includes keeping vigorous herbaceous perennials in check. The fertile boulder clay in the couple’s garden is appreciated by weeds as much as by ornamental plants. A routine late-afternoon pursuit, after the main gardening work of the day has been completed, is to conduct a socalled ‘big game hunt’ in one or other of the numerous borders. A thigh-high thistle or other opportunistic invader is often espied and uprooted. It is, of course, a pleasure to allow some plants to take hold and spread around, for they are always at their best when seen en masse. House guests up and about before breakfast are almost always a thorough nuisance, to which count I plead guilty. By 7.15am I was in the garden. The sun had just risen and its low, slanting rays were matched by my low, prone position as I photographed the most floriferous of several large colonies of Cyclamen hederifolium in a sunny border (see pages 308 and 309). There are also lavish stands under apple trees and wherever ants have carried the seeds. Although a single colour phase can be dramatic – Kit Grey-Wilson once told me that in northern France he had been astonished to find woodlands where f. albiflorum had formed a chaste monoculture – it’s the undisciplined mix of purple, pink and white that I enjoy most. Given congenial lighting, especially in the early morning and evening, the flowers appear illuminated, and even a stray dandelion tuft takes on an unfeasibly distinguished demeanour. A short distance away, but down 316
a part-shaded slope that doesn’t see the sun until mid-morning or later, a select array of summer-starting, autumn-continuing plants has been fostered. Epilobium roseum and several other rampant willow herbs I pull up at every opportunity, but just a few of its relatives are a different matter. It’s some years since I last saw Joe Elliott’s E. ‘Broadwell hybrid’ (of New Zealand parentage, involving E. glabellum and E. chlorifolium, with large, creamy, funnel-shaped flowers, flushed pink) but European Chamaenerion (Epilobium) dodonaei is a fine late performer in its own right. In its dwarfer forms it is only 30cm or so tall and provides a long succession of rich, pink flowers throughout the second half of summer and beyond. When it first appeared, over 40 years ago, the Sino-Himalayan genus Strobilanthes was littleused horticulturally, but latterday introductions from throughout the range of the genus, eastwards to Taiwan, have uncovered its offbeat ornamental value. Best of all is long-flowering Strobilanthes attenuata, a low-growing, 25-40cm tall, violet-blue flowered Nepalese stalwart (it also occurs further west in the Himalayas, at up to 3,600m). It is in bloom from midsummer until October, its ongoing September display coinciding in Rod and Jane’s garden with that of white-flowered, Japanese Oxalis articulata f. crassipes ‘Alba’. Both are best sited in partial shade, planted on a slight slope in order to stave off waterlogging, and given a half-strength liquid feed to bolster their performances. The Strobilanthes is one of numerous THE ALPINE GARDENER
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An autumnal tapestry in the garden of Rod and Jane Leeds SEPTEMBER 2015
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Strobilanthes attenuata with Oxalis articulata f. crassipes ‘Alba’
plants that the Leeds obtained from Washfield Nursery, Elizabeth Strangman’s hugely influential establishment (she retired in 1999, to widespread dismay), where they made regular visits. Other Washfield plants that have settled down well ‒ and are now available from a few other sources ‒ include several uncommon ferns (planted out in a small greenhouse, subtle additions to a diverse collection of hepaticas) and that dwarf, deciduous, distinguished spindle tree, Euonymus cornutus var. quinquecornutus. Her catalogue described it as a ‘rare shadeloving shrub from western China, slow growing to 3ft [1m]. Slender-stemmed 318
and narrow-leaved, each branch carries many large, green, horned fruits which are quite beautiful when opening to show the brilliant lining of each capsule with its pendant orange seed’. Sometimes it crops so abundantly that the branches are weighed down, so staking may be necessary. Frost, winter dormancy, the routine tidy-up that follows the shedding of the deciduous tree canopy, and the marginally less frantic pace of winter chores in the garden mean that in many gardens, spring is the most orderly of the seasons. Without judicious intervention, the autumn garden can be an untidy shambles. As an example, we illustrate THE ALPINE GARDENER
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Above, the dwarf and deciduous Euonymus cornutus var. quinquecornutus Left, Colchicum ‘W.A. Constable’ amid the leaves of Anemone x hybrida
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The Mediterranean lime-lover Eryngium amethystinum var. euspinosa 320
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The spidery flowers of Eurybia macrophylla tumbling over Primula beesiana
a stand of Colchicum ‘W.A. Constable’ (named for the Paddock Wood nurseryman and founder member of the RHS Lily Committee; nothing to do with the Suffolk artist John Constable) that has managed to produce its flowers just ahead of the enveloping leafage of Anemone x hybrida. Another week, and without a thorough cutback of its congener, it would be subsumed. Given the restraints of occasional intervention and selective pruning, the unruliness of certain plants can be harnessed to advantage. Eryngium amethystinum var. euspinosa, a limelover from the Mediterranean, comes later in the year than most of the SEPTEMBER 2015
genus, and its long-lived clumps need the support of pea sticks if you wish the stems to remain upright. If not, the weight of the topgrowth causes it to splay, rather attractively in some instances, for if sited on a ledge or welldrained slope, with the sun illuminating the metallic violet flowers, it is as if a spotlight has been trained to focus upon its performance. The stock shown here, of Italian origin, represents a seed collection made at 900m in Tuscany, where a substantial population was found growing in grassland. Climbers, too, can convert by default to sprawlers and spreaders, as John Treasure demonstrated long ago with 321
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Cardiocrinum seedheads and autumn foliage
his Clematis borders at Burford House Gardens. Tropaeolum speciosum will happily mantle dwarf rhododendrons (the glaucous or grey R. ‘Blue Silver’ and R. lepidostylum are the best of foils for its scarlet flowers) but the pairing will only work when these are long-established. With its annual growth measured in metres, the Scottish flame flower would overwhelm younger specimens. Another energetic performer, the North American usually seen under the name Aster macrophyllus (Eurybia macrophylla of late), grows up to a height of 1.5m in open woodland, yet looks best when allowed to topple over, as in the stand illustrated on page 321. 322
The corymbs of spidery flowers mask a stand of Primula beesiana, whose own moment of glory took place back in June. A dozen years ago, a survey of particularly loathed and loved plants that elicited the views of numerous rather grand gardeners sticks in the mind chiefly for the declaration of a self-evidently formidable woman: ‘I like plants how I like my men to be: controllable.’ Good heavens! Although Cyclamen hederifolium received a favourable mention, over half the selection of bestloved plants were spring-flowering, and only Cardiocrinum figured among the later-flowering contingent of bulbs THE ALPINE GARDENER
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Colchicum speciosum picking up after a storm
and corms. While this last is impressive both in flower and in fruit, it is the rich assortment of dwarfer, truly autumnal monocots that I wish to celebrate here. Colchicums, the larger and later in leaf at any rate, would presumably be ruled out by the just-quoted virago. The foliage produced by an established clump is considerable and latterly unruly, while the flowers are soon subject to the vagaries of the season, and as such are only pristine for the first few days after their emergence, albeit produced in salvoes over a fortnight or so. Strong winds and/or heavy rain will fell them. The tidy-minded gardener, who goes round daily dead-heading roses, SEPTEMBER 2015
mowing the lawn to bowling green perfection and precisely pruning topiary figures, will add the removal of these prone flowers to his or her schedule. The rest of us will perhaps simply clear away the worst of the damage, but otherwise quite enjoy the mix of the old and the new, the upright and the splayed, as is the nature of such plants. With readily obtainable, readily grown Colchicum speciosum as seen in the highlands of north-eastern Turkey (it also occurs in the Caucasus and Iran), the surrounding spent herbage helps to conceal such collateral damage. Under garden conditions, the apron of prone older flowers that a mature 323
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Iridescent Colchicum ‘Rosy Dawn’ at the Royal Botanic Garden Edinburgh
clump will soon accrue in the first weeks of September provides a study in the horizontal as well as the vertical, at least for the short while that they retain their colour, before turning to mush. Divided and re-set every three or four years, this and other vigorous colchicums will form not just lusty clumps but veritable floral carpets. C. ‘Rosy Dawn’ is one of the showiest, and our picture shows a spread some 3m wide and through, much visited by bees. This incomparable stand, at the back of the rock garden in the Royal Botanic Garden Edinburgh, was much-admired and in great demand – any number of toddlers, tourists and grandparents 324
were plonked in front of the iridescent photographic backdrop. There is a palpable need for a monograph on the genus, encompassing both its latterly expanded number of species and its clones. Plans are presently afoot, which with any luck will come to fruition before those who are expert in the diversity of the genus and are knowledgeable about its range both in gardens and in nature reach their dotage. Some of those widely grown are instantly identifiable, such as C. autumnale ‘Album’, affectionately but slightly disparagingly referred to by aficionados as ‘Bones’ on account of its ivory, bleached and somewhat skeletal THE ALPINE GARDENER
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The bleached and skeletal flowers of Colchicum autumnale ‘Album’
flowers. Others are routinely distributed under false identities, or have been confused even in the most august of gardens, so that their labellings are manifestly incorrect. The 1990s Felbrigg Hall RHS trial went some way to sorting out the widespread confusion. The ongoing Hyde Hall reappraisal, involving pretty much anyone well-versed in the genus living in the British Isles, has made a promising start and is in its second year. However, not only has a considerable new range of hybrids come on the scene to rival the finest produced over 50 years ago by R.O. Backhouse, J.J. Kerbert (these dating from twice as long) and several SEPTEMBER 2015
others, but the number of species, too, has expanded. Named in 2007 by a noted researcher, Karin Persson, C. antepense, C. ignescens, C. lagotum and others have not been mentioned in this journal previously. The list could easily be extended. They are represented in cultivation only in a very few botanic gardens, in other highly specialist collections, or not at all. As with Colchicum, some stocks of autumn crocuses are misnamed or jumbled. The 2012-14 trial at RHS Wisley was revealing but disappointing, with numerous accessions, whatever the name attached when supplied, proving to be undistinguished examples of C. 325
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Crocus kotschyanus requires settled weather to put on a good show outdoors
speciosus. (Others, correctly named, were pilfered.) It is best to purchase from a specialist nursery that either raises its own stocks or sources material discriminatingly. Otherwise, raise corms from seed. The Crocus Group has an excellent seed list and membership is not by invitation only, as was once the case. Contact secretary Tony Goode by email at tonyg@thealpinehouse.fsnet. co.uk – the joining fee is a paltry £5. Or you might know someone with a good collection who is willing to exchange or donate material. Standing straight as sentries on a fine day, soon after emergence they can be 326
felled by blustery conditions, and in any case most will not open until the sun shines and temperatures rise. Others have extravagantly large perianth segments; the outer ones up to nearly 8cm in some forms of Crocus speciosus, with C. kotschyanus not far behind. Their styles are predominantly frilly or exaggerated and brightly coloured – think of C. banaticus on the first count, and the saffron group on the second. Some have longer perianth tubes than any of the spring-flowering species – C. goulimyi, C. nudiflorus and C. niveus for example – to over 20cm in extreme cases. Pray for good light and settled weather, when they will provide a show THE ALPINE GARDENER
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Crocus speciosus in Ian Robertson’s Dorset garden
that makes one wonder why they aren’t grown more widely. I’ve mentioned Crocus speciosus, and can recall (but not track down, try as I might) a black and white photograph of this stalwart species growing by the thousand in a gravelly border, as freely and spectacularly as C. tommasinianus in SEPTEMBER 2015
late winter. But much smaller groupings can be very effective as well. The one illustrated here is in the Dorset garden of Ian Robertson, where he has built up a celebrated collection of Cyclamen, hardy bulbs (Narcissus and Crocus especially) and much more besides. Outdoors, often as not around the bases of trees, in 327
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Ian Robertson’s pot of pristine Crocus niveus Below, Robert Rolfe’s Crocus mathewii HKEP 9291
a small orchard and elsewhere, autumnflowering colchicums and crocuses abound. These reach their apogee in the first half of October. Crocus speciosus is plentiful, and stands of C. kotschyanus var. leucopharynx are a delight, as seen on the back cover of this issue of The Alpine Gardener. The varietal name was coined in 1948 and translates aptly as ‘white-throated’. Ian’s greenhouses and frames are cleverly screened to either side of the house, and the main polytunnel has a central and side beds arrangement at ground level. There are relative newcomers such as the celebrated south-west Turkish C. nerimaniae and C. wattiorum, but on the morning of my visit it was southern Greek C. niveus that was at its very best, while nearby C. banaticus ‘Snowdrift’ ran it a close second. This clone certainly increases much better from cormlets than almost any other and I can think of several 328
gardens where it grows very well indeed. My once ample stocks were killed when their pots froze through, so it was a very pleasant surprise when several flowers showed themselves last autumn, in the unorthodox conditions of a rather dry bed close to the house ‒ I must have scattered the spent potting compost THE ALPINE GARDENER
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Crocus nudiflorus ‘Orla’ departs from the purplish template of the species
there, failing to notice the few scraps of life they harboured. C. mathewii (also grown outdoors in Ian’s garden, unusually) is well represented from a 2007 sowing. Even its seeds ‒ blackish and several times as large as some of the C. biflorus alliance, for example ‒ are distinctive. C. mathewii in some examples has a very pronounced, sweet scent: ignore the falsehood that suggests otherwise. Not all expressions of this rather controversial species are easily separable from C. asumaniae, or (it has been SEPTEMBER 2015
suggested) C. pallasii. Four years from sowing, a potful of seedlings descended from the type collection (HKEP 9291) flowered for me in early October last year, demonstrating that even from this origin the throat isn’t always deep violet. Sometimes it is unmarked, in other cases brownish-tinged, like a five- dayold bruise. The white segments can also be bluish (‘very rarely soft lilac blue’ according to the original description), markedly so in a few cases, such as ‘Karin’ from Gothenburg (JKP 98 116) and ‘Dream 329
THE ALLURE OF AUTUMN Dancer’, not uniform but the most widely available. I saw a nurseryman’s stand where over 30 corms were being offered last September, the shoots well developed and full of promise. There are few autumn-flowering crocuses that disappoint, if their flowering coincides with fair weather. The white ones typically have a glistening appeal. Much-vaunted C. goulimyi ‘Mani White’ I find among the least exciting, for the flowers are rather small in relation to the length of the perianth tube, the white less brilliant than some of its rivals. Of these, first in the pageant in early September comes C. nudiflorus ‘Orla’, Joy Hulme’s lovely Pyrenean selection, in limited circulation and the only cultivated one I have seen that departs from the purplish template of that species. There’s a Crocus Street in Nottingham, close to the city centre ‒ the very last place you would ever search for such plants, although C. nudiflorus still grows a few miles from where I live, one site close to a mobile home encampment. For those who feel that enumerating one albino after another verges on collector-mania, I conclude with C. pulchellus in its typical lilac phase. A personal favourite that I’ve grown some 40 years, it was found by John Marr and his party close to the same petrol station outside Edremit that I once reached after a lengthy walk, having overshot my intended destination and disembarking from an overnight coach, miles from anywhere. It is another species that prefers not to be dried out severely when at rest, and its 330
seed has been carried by ants to various parts of the garden, with a raised sand plunge behind my garage especially to its liking. I made mention earlier of a ‘big game hunt’ in a gardening context, translating as a search for the largest undetected weed. Those who go on African safaris refer to the ‘big five’ – leopard, lion, buffalo, elephant and rhinoceros – whereas autumn bulb lovers will substitute the five genera on which their attention centres: Crocus, Colchicum, Sternbergia, Cyclamen and Nerine. The last of these has so far not been mentioned in this article, and it’s true that N. bowdenii is the only one likely to settle down in gardens throughout the British Isles. I have very happy memories of the tableaux of bright red, every shade of pink and white N. sarniensis staged in October or November by the now-no-more Newchurch Nerines (Springbank Nursery, Isle of Wight), but this is a species from low altitudes that is distinctly frost-tender, even when hybridised with its south-east African counterpart. Of N. bowdenii E.B. Anderson wrote: ‘For ease of cultivation, rapid increase, and regular flowering in the autumn, no bulb exceeds it… All it asks is a reasonable amount of sun and a welldrained soil. It is hardy at least as far north as Perthshire… Plant the bulbs an inch or so deep, in March, and divide them the same month when they become too crowded.’ There’s a garden near where I work, full of hollyhocks, bearded irises and other hardy perennials and biennials, along with a large number of old-fashioned THE ALPINE GARDENER
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E.B. Anderson declared Nerine bowdenii to be hardy as far north as Perthshire
roses. As the summer display wanes, all the clumps are ruthlessly tidied and the spent spikes hoicked out. Then, a few weeks later in the last days of August, the only briefly bare soil is again covered, this time by drifts of the ethereal nerine, which from a distance, in the soft light of early morning, form a pink mist under the standard-trained roses. Some of the best clumps I’ve seen were in eastern Scotland, the tops of the congested bulbs – they are gregarious and like a degree of overcrowding − projecting out of the ground (bury the bulbs in a manner standard for many SEPTEMBER 2015
other monocots and they will perform very poorly indeed). Also present in dazzling form were displays of Hesperantha (Schizostylis) coccinea in a rich orange-red form, looking too exotic to be hardy, although it most certainly is. For all that its upper altitudinal limit lies at around 1,800m, well below that of Nerine bowdenii, it has sailed through the worst of winters and is more likely to suffer if left short of water during the summer. Repeatedly it grows close to water, along stream banks and in damp areas, which underlines its thirsty nature. While it is available in a range of colour 331
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Scarlet Hesperantha (Schizostylis) coccinea blazes in autumn
forms, from the soft pink of ‘Viscountess Byng’ (named for a presidential figure from the Society’s past) through several dozen others – early and late-flowering, white through to scarlet – it is the colour extremes that associate and contrast best with the Nerine, handily attaining much the same height of around 60cm. This has been a bulb-fixated romp through a cross-section of autumnflowering plants. As a last-gasp counterbalance, mention should be made of a few of their dicotyledonous associates. From a gardening point of view, the best of autumn includes the vivid reds, oranges and russets of deciduous trees, cooler nights, the very rapid, widespread 332
reawakening of aestivating plants, ‘back to school’ gatherings at flower shows and conferences, and seed sowing following a successful harvest, the generosity of friends in this respect or the yield from a seed list. Autumn is chrysanthemum time for some gardeners, though not for me. But other Asteraceae provide continuing interest at this time, with the long-lasting flowers of Leontopodium japonicum still hanging on, the dark stems contrasting with the foil of autumn-coloured foliage. Saxifraga cortusifolia, also from Japan (Honshu, Shikoku, Kyushu) with its two exaggerated lower petals and crisply-cut leaves, is best sited in at least part-shade THE ALPINE GARDENER
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Above, the long-lasting flowers and dark stems of Leontopodium japonicum Right, Saxifraga cortusifolia is best in at least part-shade and kept well watered
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Above, the subtle blue of Gentiana ‘Strathmore’, happy in lime-free and moistureretentive soil Right, carpeting Acaena inermis puts on a long display
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The abundant fruit of Sorbus graeca McBeath 2671
and kept well watered (and inoculated against vine weevil), whereas carpeting, dwarfer Acaena inermis needs a sunnier spot, and will have been in good display since July. Autumn gentians certainly grow well beyond their acknowledged northern and Hibernian fastnesses – they were once sent in bunches to Covent Garden from Sussex and the West Country. I bought several from smart, onetime Sloane Street florists Pulbrook & Gould, and recall Paul Ingwersen selling them (more affordably) at Vincent Square autumn shows. The deep blue ones are most favoured, but the subtler shades of palish G. ‘Strathmore’ and others are SEPTEMBER 2015
worth considering if you have limefree conditions and can keep them well watered. Dwarf and moderately dwarf shrubs also play their part, with Corylopsis pauciflora leaves turning golden yellow late in the season, though I would also like to add to the list Sorbus graeca, less spectacular than some its Chinese relatives, but ideal if you want a small tree around 3m tall at maturity, with low boughs and an abundant crop of fruit. The example illustrated, bearing the collection number McBeath 2671, is among the best of its kind and should be more widely grown – a comment that applies to many of the foregoing. 335
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eptember marks the passing of summer. The evenings draw in, temperatures cool and there is an expectation of rain. Here on the Weald in West Sussex this brings welcome respite from the heat-induced lethargy and drought conditions which often occur in July or August. The garden reawakens and it is time to get things shipshape before the leaves start to fall. For me September 2014 was a month to remember: misty mornings, still sunny days and just sufficient rain to moisten the ground and bring the lawns back into growth. The autumn bulbs flowered with exceptional freedom, unspoilt by wind or heavy rain. Growing among them, three old friends gave particular pleasure: a crocus, a kniphofia and a nerine.
Crocus speciosus ‘Albus’
I was given a single bulb of this elegant white-flowered crocus in 1974, part of a generous gift of crocuses received when I was establishing our garden here. Many of these have fallen by the wayside on our acid greensand but Crocus speciosus ‘Albus’ has stood the test of time in every way and is a favourite among the autumn flowering Crocus species. C. speciosus has a wide distribution spreading east from Greece, both to the north and south of the Caucasus, to reach northern Iran. Within this large area it is variable with a flower colour that approximates to a lilac-blue; white flowered forms are said to be extremely rare. It seems that Crocus speciosus ‘Albus’ is probably a selection from wild material 336
Three reasons to celebrate September Peter Erskine recommends three choice plants that are first-rate performers in the autumn garden and raised in Holland. I grow it in sunny, well-drained positions among trees or shrubs and with low-growing plants in mixed borders. Unlike C. speciosus, which spreads around the garden quite profusely from seed, I have never had seedlings from this white cultivar. Relying on vegetative increase has ensured a uniform population but it means moving corms to colonise other parts of the garden and as a precaution against damage by rodents. C. speciosus ‘Albus’ generally flowers in late September. It is available commercially at a modest price and has a well-deserved Award of Garden Merit.
Kniphofia galpinii
The kniphofias occur predominantly in South Africa and are largely found along the mountain ranges and in moist places in the eastern part of that country. They range from robust rather coarse plants to much smaller species, neat and with considerable charm. Among these smaller species are K. triangularis and THE ALPINE GARDENER
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The elgant white goblets of Crocus speciosus ‘Albus’
the superficially very similar K. galpinii. Indeed Leslie Codd, who worked on the botany of kniphofias in the 1960s, considered placing K. galpinii as a third subspecies of K. triangularis and it seems that much of the material grown as K. galpinii is actually K. triangularis. Not that I think gardeners need worry too much, for Graham Stuart Thomas described K. triangularis as a plant of great garden value; not, I suggest, in the rock garden but as a front-of-border plant and very suitable for the small garden. My stock of K. galpinii was acquired in 1973 and I understand that it was originally bought from Washfield Nursery in the mid 1960s. It seems to SEPTEMBER 2015
match Codd’s description of K. galpinii. However, the differences that separate it from K. triangularis are small (The South African Species of Kniphofia, L.E.Codd, Bothalia, volume 9, 1968). These kniphofias grow in open grassland in quite rich soils, generally over basalt or sandstone. They have summer rainfall – those who have walked in the Drakensberg in summer will remember the fierce thunderstorms – and relatively dry winters with frost at the upper limits of their distribution. I have grown K. galpinii without any protection, in full sun on a light, welldrained acid soil with a top-dressing of old stable manure in spring and 337
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The freeflowering South African Kniphofia galpinii brings vibrancy to the garden in autumn
an occasional sprinkling of slowrelease fertiliser. It flowers freely in late September or early October, with the tallest flower stems reaching about 60cm, and may be divided in spring.
Nerine undulata
In early November 1991 I stayed with Dr Clive Boyce at his recently acquired 338
home near Bury St Edmunds. In the garden there were several substantial clumps of a Nerine which we concluded was N. undulata or something close to it. It seemed to be hardy and vigorous. I was given some bulbs and here, on acid greensand, these have been very successful in well-drained sunny sites and with quite rapid vegetative increase. THE ALPINE GARDENER
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The hardy and vigorous Nerine undulata, with heads of 15-20 flowers on each stem
This nerine is very floriferous and mature bulbs carry heads of 15-20 flowers on 60cm stems – a first-rate garden plant. It is generally summer dormant with fresh foliage appearing in late September, shortly before flowering, and this dies down in early spring or as a result of winter cold. I took two flowering stems to the Hardy Nerine Study Day at Wisley in October 2007. These were identified as N. undulata Alta Group and subsequently bulbs have become commercially available under that name. There is, however, no modern treatment of the SEPTEMBER 2015
N. undulata complex and the range and variation within it does not seem to be well understood. In my view the use of the epithet N. undulata Alta Group is not sufficiently precise for naming a garden plant and also may be considered misleading, as there seems to be little affinity with N. alta. N. undulata Alta Group is currently being evaluated in the Hardy Nerine Trial at Bramdean and Acton Pigot. Subject to the final outcome, a cultivar name will be proposed so that this excellent garden plant can be more precisely identified. 339
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iven a sunny spring morning, it is a joy to wander, coffee in hand, through areas of the garden that accommodate various crocus species. Fleeting though their display may be, it is something I look forward to in the dark days of winter. In spring, however, so much else is happening in the garden that they receive less of my attention than the autumn-flowering species. By late October, most of the garden is flowerless as plants prepare for winter; what flowers there are tend to be past their best. The sudden appearance of pristine flowers is something I allow more time to savour, knowing that flowerless days are not far off. Crocus nudiflorus is the first to appear, from early September onwards depending on soil moisture levels. Unlike many crocuses it does not need a dry summer spell, so bulbs in moist and cultivated places may be in flower several weeks before those in a dry spot under trees. Here it grows in areas of differing aspect and soil types, so there is a good succession of rich, purple flowers. There is also a lovely white form here, not quite so vigorous. On a shady clay bank of grass, C. nudiflorus has spread slowly, but it has romped through a humus-rich bed, making the most of its stoloniferous habit. The leaves which follow are fine in all places for the winter, but in spring do look untidy in cultivated areas among various plants which may be looking immaculate. I cannot wait to remove them the moment they start to turn yellow. C. speciosus varieties, C. pulchellus
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Late crocuses that never fail to delight Notes from Hampshire In his occasional column, Robin White reflects our seasonal theme by relating experiences with autumn crocuses and C. pulchellus ‘Zephyr’ do well in both open woodland and grass, which is mown once in late August. Both areas provide a drier summer rest than other parts of the garden. These species and C. nudiflorus can suffer in our autumn weather due to their long perianth tubes, which cannot stand up to heavy rain and strong winds. Maybe in their natural habitat they have evolved to push up through surrounding vegetation. Trying to find companion plants to provide support and which will tolerate grass (recently mown), or woodland with the dry summer conditions, is difficult. It is important that support plants do not have deep root systems that will compete with the crocus bulbs too much. Since C. nudiflorus will tolerate damp summer conditions, I have used Saxifraga fortunei, Persicaria THE ALPINE GARDENER
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Violet-scented Crocus ligusticus flowers well in grass and under birch trees
vaccinifolia, Cyananthus lobatus and Geranium wallichianum to support the flowers. The last mentioned does have a deep taproot, but pushes its flowering growth out over a wide area where it does not compete with the bulbs. Cyclamen hederifolium is one of the few species I have identified as a suitable support in the woodland; by October its leaves are well developed, making a lovely background for the crocus flowers. Where we have areas of gravel bed or basic rock garden there are numerous mat-forming plants – Phlox, thymes, Aubrieta and Veronica austriaca to SEPTEMBER 2015
mention a few – that will provide support for the flowers of various crocuses requiring a drier summer and also help to protect from extreme cold the corms of some species considered tender. Two mid-season species are my favourites – C. banaticus and C. ligusticus (formerly C. medius). If for nothing else, I would treasure C. ligusticus because it was given to me by Kath Dryden with the information that it was the Oliver Wyatt form. The flowers are sturdy enough to cope with autumn gales, dark mauve with a brilliant orange/red style, 341
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Crocus goulimyi is thriving among Daphne x hendersonii in Robin White’s ‘daphnetum’
and sunny days will find me down on my knees to savour the strong scent of violets. I have read that most forms of C. ligusticus in cultivation are infected with virus, but I can see no obvious symptoms, and the bulbs increase and flower well in grass and under birch trees, both summer-dry locations. Initially, I struggled to grow C. banaticus well, probably allowing the 342
corms to get too dry in summer, since this species from the meadows of eastern Europe prefers a fertile soil which does not receive an annual baking. Fresh stock planted in humus-rich areas shaded from the hottest sun has thrived and set plenty of seed. For anyone who would like to increase their stock of this beautiful plant, it is well worth saving and sowing seed thinly in a large pot. THE ALPINE GARDENER
THE ALLURE OF AUTUMN Given some liquid feed in each growing season, flowering-size (quite small) corms can be produced in three years. My plants range from pale to dark mauve, with a few of the super white clone ‘Snowdrift’. The flowers survive upright in a sheltered spot, but do benefit from some support in a windy autumn. A planting among corms of silver-leaved Cyclamen hederifolium has proved very successful. Even if the flowers do not coincide, the silver foliage provides a wonderful foil for the soft mauve crocus flowers. I first grew another mid-autumn species, C. goulimyi, in pots plunged in the sand of a bulb frame. As it comes from southern Greece, I thought it would need some winter protection. The mauve and white forms increased rapidly, thriving on lack of attention, with escaped bulbs and seedlings settling down in the sand. This generous behaviour allowed me to try bulbs outside in a gravel bed and in the Cotswold pea gravel of our ‘daphnetum’. In the former area bulbs are thriving under Thymus serpyllum. With their long perianth tubes, flowers in the ‘daphnetum’ push through lowgrowing varieties such as Daphne x hendersonii ‘Jeanette Brickell’. To date, I have been lucky enough to avoid severe mice and vole damage to my crocus corms, but their foliage, particularly that of C. goulimyi, seems to attract the rodents’ attention. Late autumn heralds the appearance of C. niveus, with large pure white flowers, and C. tournefortii, whose pale mauve flowers remain open irrespective of the weather. I accept that both these species are best appreciated when grown with SEPTEMBER 2015
Crocus niveus rising through thyme
some overhead protection. But, grown in the gravel bed under mats of other plants to protect their bulbs, they survive and, if the weather is kind enough, their flowers are much appreciated. C. tournefortii also does well under the birch trees. At a time when I can find few flowers in the garden apart from some snowdrops and the odd precocious Cyclamen coum, what a boost it is to discover a small, pale mauve crocus with dark feathering on the outside, the flowers wide open as soon as the temperature approaches double figures. I think it is a form of the variable C. laevigatus, with flowers appearing sporadically from late November to early January. They survive, but do not seem to increase much – maybe those mice are responsible. I must try to get some more established. 343
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elected forms of ‘mossy’ saxifrages such as S. cebennensis and S. pubescens are exhibited year after year at AGS shows, yet their South American counterpart S. magellanica is seldom shown and its horticultural worth has generally been downplayed. Mark Childerhouse’s defining plant, awarded a Certificate of Merit at this year’s Chesterfield Show, was full of flower in the way of its European counterparts, even if its mat of foliage couldn’t match their hemispherical precision. This mainly Andean plant has a distributional range of at least 3,500 miles north to south, and is in effect an amalgam of races and ecotypes, some with good-sized, glossy white flowers and a compact habit, others with longer stems and loose cymes of flowers lacking in purity and appeal. Those familiar with the species in the wild say that the finest examples predominate in the south of its range, around the Strait of Magellan, after which it was named some 200 years ago. Supporting this theory, Mark’s plant was an introduction by Ger van den Beuken from Tierra del Fuego that has proven floriferous (it had been in partial flower months before the mid-April show date) if kept slightly pot-bound, its lean compost never left short of moisture. At this latitude it occurs from sea level to around 1,200m, typically on basalt cliffs and outcrops,
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A southern saxifrage 2015 SHOWS FEATURED: Northumberland, South West, Cleveland, Chesterfield, Dublin, Midland COMPILED FROM REPORTS BY: Angie Jones, Graham Nicholls, Chris Lilley, George Young, Jim McGregor, Dave Riley
though it has also been recorded from roadside ditches, moorland niches and even Nothofagus woodland. The species was known to Andean plant pioneer Harold Comber, but I can find no record of it having become established in cultivation from his or any other early gatherings, and to this day it is found only in a few specialist collections. Serendipitously, at the same show Chris Bowyer staged a plant of different provenance. This, with smaller, cream-tinged flowers and larger, paler rosettes, had been grown outdoors for years: cold-hardiness is not in doubt. Most accounts record S. magellanica from Chile and Argentina north to Peru, at a maximum altitude of 3,000m. A string of synonyms and lack of access to regional checklists have presumably
Full show reports and more pictures can be seen on the AGS website THE ALPINE GARDENER
FARRER MEDAL WINNERS 2015 NORTHUMBERLAND Trillium rivale ‘Purple Heart’ (Cyril Lafong) SOUTH WEST Dionysia ‘Inka Gold’ (Paul and Gill Ranson) CLEVELAND Dionysia michauxii (Derek Pickard) CHESTERFIELD Astragalus coccineus (Peter Farkasch) DUBLIN Draba longisiliqua (Val Keegan) MIDLAND Benthamiella patagonica F&W 10111 (Eric Jarrett)
The ‘mossy’ Saxifraga magellanica, which won a Certificate of Merit for Mark Childerhouse at this year’s Chesterfield Show
put some researchers off the scent. There are sound records from East Falkland at one extreme (where it is very rare) and the central to northern Andes at the other, with some Peruvian occurrences approaching 5,000m, in the Cordillera Blanca and beyond. Engler and Irmscher confirm it from further north, in Ecuador (using the name S. cordillerarum f. stellata for material from El Altar at 3,900-4,300m) and also, perhaps unexpectedly, Colombia. I’ve seen it at over 4,000m in both southern Bolivia and Peru, once in SEPTEMBER 2015
seasonally parched rock crevices, more recently in 2012 on a rock face saturated by a waterfall, while a trawl of fairly recent records shows that it is present in Ecuador from Azuay province (S. andicola and S. peruviana are aliases) at least as far north as Pichincha, overlooking Quito and almost on the Equator. One 2009 report gives the distribution as Venezuela down to Fuegia. While not inconceivable, this extension needs verifying. Robert Rolfe 345
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Pictures: Mike Dale
Primula erosa (John Richards) Once considered a variety of P. denticulata, and in effect an elfin, evergreen but much scarcer version of the widespread Himalayan, P. erosa has had a chequered history in gardens since its first introduction around 1820. It appreciates a humus-rich, perlite-leavened compost and has a long flowering period. Iris willmottiana (Brian Burrow) Described from Ellen Willmott’s Essex garden at the start of the last century, this PamirAlai/Karatau species is mainly represented in cultivation from Kazakhstan accessions, with one or two from Uzbekistan for good measure. Each shoot produces up to eight flowers in succession, steely to cobalt blue with a white signal patch and variable darker blue blotching and striping. Saxifraga ‘Coolock Gem’ (Mark Childerhouse) One of several saxifrages shown by the exhibitor, this was the largest of all, eclipsing even a formidable specimen shown by Frank and Barbara Hoyle. The Certificate of Merit awarded possibly marks its last such accolade, for it now occupies a pot at the 36cm limit and is incredibly heavy! 346
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SOUTH WEST SHOW
Pictures: Jon Evans
Dionysia ‘Inka Gold’ (Paul & Gill Ranson) A hybrid between D. odora and (in all likelihood) D. tapetodes, raised by Michael Kammerlander from a 2003 sowing, ‘Inka Gold’ has flowers of a particularly rich yellow. The exhibitors were given a plant by Michael nine years ago and have grown it to such a standard that it was the clear winner of the Farrer Medal at Exeter. Tecophilaea cyanocrocus (Jim Loring) The Cornwall Trophy for the best plant in the Intermediate Section went to an exceptional pan of this Chilean native, much better known in cultivation than in its very restricted populations on dry, stony slopes in the Andes. It sets seed readily and will increase well once established. A cool summer rest in a sand plunge that doesn’t dry out suits it well. Ranunculus abnormis (Joy Bishop) In leaf more like a bulb and best treated as one, the flowers of this distinctive buttercup are up to 25mm in diameter, carried on stems that are very short at first but elongate. It is recorded from western and central Spain through to Portugal but most cultivated plants are referable to a Sierra de Gredos sampling made by the Bacons 43 years ago. SEPTEMBER 2015
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CLEVELAND SHOW
Pictures: Robert Rolfe and Don Peace
Dionysia gaubae (Geoff Rollinson) It’s difficult to overstate the impact made on the show benches by dionysias this year. The use of limestone shards as a topdressing was a clever touch, evoking its native cliffs in Lorestan Province, Iran. The last time Geoff grew it really well, a mishap led to damaged flowers. Happily, there was no repeat performance. Saxifraga columnaris (Geoff Mawson) This large, flattish cushion of the painfully slowgrowing Caucasian endemic is surely a contender for best of its genus shown this year. Nearly two decades have elapsed since the species was introduced. This specimen was obtained from Slack Top Nursery in August 1999. Anemonella thalictroides (Tim Lever) Despite all the many named forms (semi-double, fully double, pink, green and so on), a well-flowered plant of an ‘ordinary’ white version in its all too brief prime is a delight. Unlike certain other woodlanders, its scale is entirely in keeping with the high alpines with which it is sometimes juxtaposed on the show bench. 348
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CHESTERFIELD SHOW
Pictures: Don Peace
Astragalus coccineus (Peter Farkasch) Of all the hundreds, indeed thousands in its genus worldwide, this Californian/ Arizonan narrow endemic is the only one that contrasts silvery felted leaves with heads of large, scarlet flowers. It has been exhibited in the past from time to time, but surely never to the standard of this Farrer Medal specimen. Rhodothamnus chamaecistus (Ian Kidman) This entry garnered several awards, including the Frances Hopkin Trophy for the best plant in a 19cm pot. Difficult to obtain and rather tricky to propagate, there is not a more beautiful member within its huge family. Found growing on limestone in the Dolomites and the eastern Alps, it is usually cultivated in a humusrich, lime-free compost. Saxifraga ‘Allendale Duo’ (Mark Childerhouse) Teamed with yellow Dionysia revoluta and sparkling white Primula ‘Aire Mist’, this novel 1998 Ray Fairbairn cross between the seldom grown Carpathian, Greek and Anatolian S. corymbosa (S. luteo-viridis of old) and Himalayan S. stolitzkae was the central component of a three-pan entry that won its keenly contested class. SEPTEMBER 2015
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DUBLIN SHOW
Pictures: Billy Moore
Draba longisiliqua (Val Keegan) Whether judged by its silverygrey foliage or the panicles of relatively large, bright yellow flowers, few other drabas compare. It can be encouraged to grow quite quickly (but not out of character) by administering occasional dilute tomato fertiliser soakings, making sure that these do not drench the foliage, and that a draughty position under glass is chosen. Callianthemum anemonoides (Tim Lever) Various examples of this distinguished Ranunculus relative were shown in March and April – some very undistinguished, with meagre, narrow-rayed flowers. If possible, you should buy a plant in flower or from a good parent stock, such as this one. Also, select a deep pot: the root system is formidable. Meconopsis integrifolia subsp. lijanensis (Harold McBride) Possibly best ascribed to subsp. souliei, this plant had been received in 1993 from Stella and David Rankin as a seedling, representative of a population in south-west Sichuan found at 3,500m on open hillsides, among grass and rocks. To quote the Rankins: ‘Cultivation is as for other integrifolia types – welldrained, moist, plenty of feeding, and prayer morning and night. And even then nothing is guaranteed.’ 350
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MIDLAND SHOW
Pictures: Jon Evans
Dionysia caespitosa (Eric Jarrett) One of the most challenging of the Zagros Mountains species, so its Certificate of Merit was hard-won. Plants have a nasty habit of collapsing suddenly and irreversibly, and it will be necessary to mate this sole surviving ‘thrum’ with a friend’s long-styled ‘pin’ to obtain seed. On the other hand, it has hybridised spontaneously with the closely related D. gaubae, also shown by Eric. Benthamiella graminifolia (Eric Jarrett) It really was Eric’s show: he won the Farrer Medal with B. patagonica and a second Certificate of Merit for the very distinctive B. graminifolia from much further north, first introduced (F&W 10725) from Neuquen Province in 2003. Perhaps only exhibited once previously in flower (also at this venue, in 2010), it has very narrow leaves and stemless, starry, greenish or cream flowers. Primula albenesis hybrid BB 10/21/3 (Brian Burrow) Three years ago we illustrated another version of the same parentage (P. allionii x carniolica, crossed with P. albenensis). Its sister seedlings can be taller, as here, with well-filled umbels, and a useful lateflowering habit inherited from P. carniolica, just as the foliage owes much to P. albenensis. SEPTEMBER 2015
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