By Susan Belsinger

Plant Profile
Family: Tropaeolaceae
Scientific name: Tropaeolum majus
Common names: nasturtium, Indian cress, trophy cress, trophywort
Native Habitat: Peru, parts of South America
Plant Type: Annual
Growth Habit: Dwarf bushy cultivars grow from 8 to 18 inches in height, while the climbers can easily reach 6 to 10 feet, or more.
Hardiness: Hardy in frost-free locations
Light: Best in full sun; can tolerate a few hours of shade, which produces more leaves with fewer flowers
Water: Moist but not wet; will tolerate some drought
Soil: Friable and porous garden loam, well-drained soil; does well in containers
                                                                                   Propagation: Seeds in spring

“Nasturtium is an herb which for me has three uses: it lights sober herb beds with its bright colors of orange and yellow; all summer it decorates salads with leaves and gay flowers; and in the autumn it provides green seeds for pickling. Does it not earn for itself a place in an herb garden?”

                                                                                                                    —Annie Burnham Carter
                                                                                                                        In An Herb Garden

One of my very favorite flowers that I grow in all of my gardens for many reasons are nasturtiums, and I affectionately refer to these garden rowdies as “nasties”. They are easy to cultivate and effortlessly fill in garden spaces with their mounds of fun foliage even before their showy colors appear. The unusual foliage has rounded, wavy-edged leaves that are attached to their stems from the underside, directly in the center of the leaves, so that they resemble fairy umbrellas. These center-stemmed leaves radiate veins from a center dot looking somewhat star-like and range in various shades of green: grey-green, bright green, blue-green, and variegated. The spurred, trumpet-shaped flowers are available in a palette of bright colors from tropical creamy yellow, peach, and coral to vivid primary yellows and reds, in addition to knockout oranges, golds and even mahogany. Many are splashed or dotted with colors and my new favorite, ‘Bloody Mary’, has a different design and range of colors on each bloom. It is said that due to the shield-like form of the leaf and the helmet-shaped blooms that the botanical name derives from tropaion, the Greek word for “trophy.” 

No wonder Monet cultivated them liberally throughout the gardens at Giverny, where he captured the mounding masses of jewel-colored blooms in numerous of his famous paintings. Thomas Jefferson planted nasturtiums in his garden every year and lamented when he couldn’t get seed enough for a bed of them measuring 10 x 19-yards. In Green Enchantment by Rosetta Clarkson, she writes of a Dr. Fernie commenting on “nasturtium flowers giving out sparks of an electric nature at sunset.” Richard Mabey of The New Age Herbalist notes that, “It is said that on hot summer days sparks are emitted from the heart of the flower due to its high phosphoric acid content.”   Others, however, have attributed this phenomenon to an interesting optical illusion produced by the interplay of our eyes and the contrast of the flowers and foliage at dusk. For further explanation, read this interesting, informative article about nasturtiums: https://heirloomcottagegarden.weebly.com/blog/nasturtium-tropaeolum-majus

We owe our gratitude to the Spanish conquistadores for bringing the fiery-colored Tropaeolum minus back to Europe from South America more than 500 years ago. The species is a vine that can easily grow about 8 to 10 feet and likes a fence or trellis for support, while the more common nasturtium cultivars grow in mounds or trail along borders, spill over walls or over the edges of containers. Nasturtiums start easily from seed in average soil and full sun; I put them in early in my Zone 7 garden (about the same time that I put in early greens) in late March, early April. I like the ritual—going about the garden with my seed packs—poking the fat bumpy-round seeds (which sort of remind me of a small chickpea) in the cold earth with my finger along the edges of the kitchen bed. I plant them anywhere from 8 inches (for masses) to a good foot apart. Keep them well watered; however, do not fertilize too much or you’ll get massive leaf growth with few blooms. Harvest leaves regularly to keep them bushy. 

I just love that their name combines the Latin nasus for “nose” and tortus for “twisted” describing how our nose twists or wrinkles when we inhale their spicy scent. In The Fragrant Path by Louise Beebe Wilder she agrees, “ …perhaps the individual odours of the summer garden are derived from certain plants which persons of hyper-sensitive nasal organs may turn from in disgust. I call these plants Nose-twisters, because the rough and heady scent of Nasturtium, which seems to have in it something bitter, something peppery, and a vague underlying smoky sweetness, is representative of them.” 

In the kitchen, you can use both the fresh foliage and flowers to add a pleasant hint of heat and pungency (this dissipates when cooked so I use them mostly fresh) to many summer dishes. The leaves are high in vitamin C and add a peppery cress-like flavor to salads, sandwiches, green sauces, or they can be shredded and tossed with pasta, rice, couscous or chicken salad, or chopped as a topping for pizza. 

The blossoms have the same pepperiness as the leaves, but are milder with a hint of floral scent. They make excellent containers for cold salads—egg, chicken, and vegetable—as well as cheese spreads. Since they are a bit fragile when filled, I tend to put them on a slice of vegetable or bread in order to pick them up easily. Whole flowers can be used in salads or as garnishes; vinegar flavored with nasturtium flowers is lovely in color and interesting in flavor; or cut flowers and leaves into chiffonade (thin ribbons) and blend with butter, or toss with egg salad, noodles, vegetables, or fish. The unopened buds, marinated in wine or vinegar, make an unusual refrigerator pickle. Seeds are harvested and pickled and used as a substitute for capers.

To harvest leaves, pick them and remove stems, wash and use like lettuce. For flowers, pick them with long stems and keep them in a glass of water until ready for preparation. Rinse blooms gently and shake or pat them dry. Pull the bloom from the stem and use whole or gently tear into separate petals. While they can stand cool weather, they will succumb to the first frost.

Sources
Belsinger, Susan and Arthur O. Tucker. 2016. The Culinary Herbal. Portland, Oregon: Timber Press.

Belsinger, Susan. 1991. Flowers in the Kitchen. Loveland, Colorado: Interweave Press.

Carter, Annie Burnham. 1947. In An Herb Garden. New Brunswick, New Jersey: Rutgers University Press.

Nasturtiums (Tropaeolum majus). Retrieved from https://heirloomcottagegarden.weebly.com/blog/nasturtium-tropaeolum-majus

Wilder. Elizabeth Beebe. 1996. The Fragrant Path. Point Roberts, Washington: Hartley & Marks Publishers, Inc.

Photos courtesy of the author. 1) Bloody Mary; 2) Alaska series; 3) Nasty bouquet; 4) Flower and herb butter

Susan is a culinary herbalist, food writer, educator, and photographer whose work has been published in numerous publications. She has authored a number of award-winning books. Her latest book, The Culinary Herbal: Growing & Preserving 97 Flavorful Herbs was co-authored with the late Dr. Arthur Tucker. Susan is passionate about herbs and her work, sharing the joy of gardening and cooking through teaching & writing, and inspiring others to get in touch with their senses of smell & taste.