Many of the dwarf lepidotes are from alpine regions so they are ideal to use in a rock garden. Accustomed to cold and snow, they are often quite winter hardy and can succeed in northern gardens where evergreen azaleas tend to struggle. However, they are usually less heat tolerant so those of us who live in warmer climates are more limited in our choices.

The most impressive rock garden I have seen is in Scotland at the Royal Botanic Garden Edinburgh. The design is free flowing and artistic. The plant materials are diverse and often rare. The entire place is immaculate. In one area, an undulating grassy lawn is planted with masses of dwarf lepidote species that fit naturally into the terrain. These are primarily alpine species. Tall evergreen trees frame the planting and small pockets of perennials and wildflowers complete the design. In another area, gravel paths wind through rock masses where dwarf rhododendron species and choice companion plants grow in a natural setting. It is so nice to be able to appreciate all those small treasures at eye level. Below are some images I took at the garden.

In the Washington, DC, area, my favorite dwarf yellow lepidote is R. keiskei from Japan (pictured left). It seems to do quite well even without careful attention. Some of the very dwarf forms like ‘Yaku Fairy’ are less forgiving but I do have 4 or 5 selections that succeed. Haag’s ‘24 Karat’ is a yellow hybrid, taller than R. keiskei, and seems very tough.

The dwarf species R. impeditum makes a lovely specimen for a rock garden or bonsai but it is very difficult to grow in warm climates. I found a protected microclimate in my garden and kept one alive for 3 years. Then a storm brought down a large tree which changed the shade pattern and it was dead within the year. R. fastigiatum looks very similar but seems equally difficult to keep alive.

The species is quite variable and flower colors can range from white, through pink, mauve, and purple, but also into the blue range with some of clearest colors of any rhododendron. The best forms are propagated by cuttings so that people get the desired clone in the proper color. David Leach noted that flower color can vary from year to year depending upon the weather. I have noticed variations in flower color in some of my photographs over the years but I know blue has been a difficult shade to capture anyway. He said if the spring was cold, flowers can be less blue and more pink. If spring is warm, the flowers tend to deeper shades of blue.

At the RSBG, there is a trail they call the "Hall of Rhododendron augustinii" that has wonderful selections of this species in many different shades. The path tunnels under tall plants and the colors blend together in perfect harmony. It is truly lovely. In the wild, this species is native to central China in the Province of Hubei (Hupeh) where Wuhan is located and continues into Sichuan. It prefers open, rocky hillsides at elevations of 4000-13,000 ft (1200-4000 m) in full sun.

The Species Foundation has posted a link to a Facebook video of their R. augustinii display taken in 2020. As they stroll under those towering rhododendrons in full bloom, also notice the masses R. keiskei 'Yaku Fairy' that serves as a ground cover in that area as well.

Frank has a large species collection but he has been a prolific hybridizer, too. The majority of the hybrids in his garden seem to be those of his own creation. He does have several forms of R. augustinii in varying shades of blue, but the real show stopper is one of his own hybrids, ‘Vibrant Violet’ (impeditum x augustinii 'Towercourt'). It is a compact plant with rich, deep violet blue flowers. He has used it in many exciting color schemes throughout the garden complementing his other hybrids.

I wish I could grow R. augustinii. There are some blues we can grow including‘Blaney’s Blue’ which can be a good deep blue, and ‘Rhein’s Luna’ which is a lighter lavender blue developed in Pennsylvania. 'Crater Lake' has succeeded in a number of gardens. That just gives hybridizers in our region focus in breeding for hardy blues.