Nikita Khrushchev gave President Dwight D. Eisenhower a gift of two European linden trees in 1960, the same year in which he ordered the American U-2 spy plane shot down over Soviet territory. International crisis erupted over the U-2 incident, and the linden trees became an awkward footnote. Now, Khrushchev’s lindens are thriving among the other herbal trees that surround the National Herb Garden in Washington, D.C., the awkwardness long forgotten.
The National Herb Garden is one of the largest gardens of its kind in the world. Covering about three acres, it showcases an enormous range of plants that have played significant roles in human lives. Many visitors leave with a greatly expanded notion of what constitutes an herb garden, as well as an appreciation for the grace and beauty that abound here. They are wont to whisper, “This is an herb garden?”
The setting is a meadow opposite the National Arboretum’s administration building, where grasses and wildflowers paint a peaceful picture. Because the site is near the main gate and parking lot, everyone who visits the arboretum passes by or through the herb garden. In fact, since its establishment in 1980, the herb garden has become the main attraction of the 444-acre arboretum, not just because of its convenient location, but because it lends itself so well to studying, strolling, lolling. It is a refuge from the bustling city.
For an idea of the size and scale of this garden, picture a fund-raising party held here last summer: 450 guests and public officials came for a clambake, drinks, and live music, and they all fit comfortably into the garden.
The stately formal garden, designed by Thomas Wirth for The Herb Society of America (HSA), is laid out in roughly the shape of an old-fashioned key. At the entrance is a brick-paved terrace about 50 feet in diameter that is edged with osmanthus hedges and thymes in semicircular beds; a reflecting pool is a central focal point. From the terrace, visitors can look down onto a sunken knot garden, and the elevated view makes the intricate pattern of the knot more visible. The 25-by-50-foot knot is a contemporary interpretation of a sixteenth-century English design. Because of its scale, the more traditional small herbs have been replaced by dwarf evergreens: spruce (Picea pungens ‘Montgomery’), false cypress (Chamaecyparis obtusa ‘Nana Gracilis’), and holly (Ilex crenata ‘Helleri’). These are considered herbs because their resins, barks, and needles have been used for medicinal or industrial purposes.
The garden path leads west to the Historic Rose Garden, a long rectangle about 50 by 80 feet that connects the two ends of the key. Many visitors are surprised to find roses in an herb garden, but herb gardeners are well acquainted with the rose’s solid standing among herbs and its usefulness through the centuries for food, medicine, and fragrance. These antique roses, which predate the advent of the hybrid tea rose in 1867, number well over 100 varieties and include some of the most beautiful and fragrant of all roses. The rose garden is bounded on two sides by holly hedges, and along another side by a trellis-covered sitting area, a favorite trysting place for lovers. The fourth side of the rose garden looks out onto the meadow through an open grouping of airy trees, all of herbal value. When the roses come into bloom for a few weeks in mid- to late May, the sight is spectacular, and they are underplanted with herbs to provide color and interest during the rest of the growing season. The variety and contrast among plantings in the rose garden vividly demonstrate that roses need not be restricted to a separate area of the garden.
The third garden space is a grassy oval about 150 feet long with ten theme gardens arranged around its rim (see “Gardens in the Garden” on page 46). Holly hedges separate the collections, which are grouped by use or association. Each garden is horseshoe-shaped and slopes up toward a stone retaining wall so that the plants in the back can be easily seen, a design especially suited for teaching and studying.
Janet Walker, curator of the National Herb Garden, estimates that these specialty gardens comprise about 1000 species and varieties, including native and foreign plants, cultivated and wild-collected species, annuals, biennials, and perennials. Roughly half of the plants are permanent, and the others are rotated or replanted to ensure new views each year.
Beyond the perimeter of the oval are herbal shrubs and about 100 large herbal trees. Some, such as Khrushchev’s lindens, have been there since the garden’s inception, and others have been added with funds raised by the HSA. The trees include a sugar maple, larch, pines, California incense cedar, black gum, sassafras, and some particularly ornamental specimens that include a cut-leaf beech (Fagus sylvatica ‘Asplenifolia’), a Japanese crape myrtle (Lagerstroemia fauriei), and a Chinese fringe tree (Chionanthus retusus) with delicate, pendulous white flower clusters followed by large blue-black berries.
The herb garden’s splendor isn’t limited to one season. Bulbs start the flower show in April, the antique roses burst on the scene in May, and then a succession of flowering plants maintains interest through the first frost in mid-October and beyond.
Gems in the Garden
The National Herb Garden provides a rich educational experience for both the casual gardener and the serious botanist, and it is a place where treasures lurk.
In the Medicinal Garden, look for Siberian ginseng (Eleutherococcus senticosus), an 8-foot bush with spiny stems, green leaves, white flowers, and a carefree growing habit. Russian cosmonauts and athletes as well as ordinary citizens use this herb as a restorative. In the Oriental Garden Zingiber mioga, a yellow-flowered ginger, draws a sentimental response from Japanese visitors, for whom it is an important culinary plant that heralds the coming of spring.
Trellised among the roses is purple hyacinth bean (Lablab purpureus), which comes into bloom in late summer. Beautiful reddish leaves set off spectacular, 8-inch-long lavender flower spikes. Thomas Jefferson grew this plant at Monticello, and its edible pods and seeds have long been popular in India, but hyacinth bean has only recently become readily available in this country.
Black horehound (Ballota nigra) interests visitors with its tiered flower stalk, its disagreeable odor, and its history as a worm medicine and antidote to the bite of a mad dog.
Cuban oregano (Plectranthus amboinicus) has cruised cuisines from the West Indies and Puerto Rico to Spain and India, disguising the strong aromas of fish and goat, complementing mints and young fruits, and flavoring wine and beer.
The National Herb Garden acquires its plants in a variety of ways. Some are purchased, some donated, and some obtained by seed or plant exchanges with other arboreta and botanical gardens. Others are collected from the wild all over the world. Walker’s priorities for garden acquisitions include eight genera of herbs, and high on the list is Salvia. More than 50 different salvias are currently being propagated in the greenhouses or growing in the gardens, including a salvia border along the walkway in the rose garden. The genus comprises more than 800 species, and their diversity guarantees an impressive display.
Other collections that Walker is working on include monardas, lavenders, rosemaries, nepetas, thymes, oreganos, and mints. One of the garden’s mints, Mentha aquatica, came from the re-created cottage garden of Anne Hathaway, wife of William Shakespeare, in Stratford-on-Avon, England.
Challenges and Rewards
The National Herb Garden defines “herb” broadly, and just about any plant except grains, vegetables, or those used only for ornament can find its way in. The plants are selected in part for their ability to survive a hot and humid summer in the nation’s capital, which can be sticky and uncomfortable for people and plants alike. The District of Columbia is in USDA Zone 7 and thus is hospitable to trees and shrubs from a relatively wide range of climates, but the 90 percent summertime humidity is hard on many of the Mediterranean herbs, which prefer drier conditions. Woolly-leaved plants are particularly vulnerable to rot. Although the garden boasts a fine display of salvias, common garden sage (Salvia officinalis), ordinarily one of the hardiest of perennials, often falls prey to soil-borne fungi and is grown as an annual here. Annual herbs such as coriander, cumin, and fenugreek bolt quickly in the summer heat, “and that’s the end of that,” Walker says.
Many of the plants coast through the usually mild winters; cuttings of tender varieties are wintered over in greenhouses, and some of the roses are mulched. Walker likes to experiment, and some tender plants surprise her by their tenacity. Some ginger that she bought in a health-food store was planted in the Culinary Garden and has been growing well ever since. Many of the rosemaries winter over successfully, and the rock rose Cistus ladanifer lives and blooms beautifully despite the humidity.
“I think it helps to test the limits of plants—to try to provide them with what they want, then see if they can make it,” she says.
Holly Shimizu, now assistant director of the U.S. Botanic Garden, was the National Herb Garden’s first curator and held that job until 1988. Well does she remember the challenge of turning that meadow into something worthy of being called a national garden. “Poor soil, poor drainage—it was like gardening in cement. And it took a long time, at least five years, to get the sense of its being a garden.”
Shimizu recalls the garden’s first summer, when it was a bald, scrawny patch. The weather was so hot and dry that she couldn’t keep up with the watering and everything shriveled. But gradually the woody plants and shrubs took root and settled in, and each year the garden grew more lush as the staff worked organic matter into the bricklike soil and added new plants.
The garden is now a blossoming teen-ager, and it is heartening to those involved in its planning and planting to see it take on its own character and ambience and start to show signs of maturity. Even the city wildlife has discovered the garden: birds, foxes, rabbits, snakes, and hawks can sometimes be spotted on the grounds.
The herb garden requires fairly high maintenance. Because the goal is strong, healthy plants, they are fertilized regularly. As part of an integrated pest management program, the garden is monitored for insect and disease problems, and alternative controls such as beneficial insects are used as often as possible. But if an individual plant’s life or vigor were threatened, stronger measures would be taken.
Walker oversees all aspects of the national garden and its small staff, including garden maintenance and development, educational programs and workshops, a corps of regular volunteers, and contact with the public. She gets her hands in the soil when she can.
The arboretum can be found at 3501 New York Avenue in the northeastern section of the District of Columbia. It is open every day of the year except Christmas from 8 a.m. to 5 p.m. weekdays and from 10 a.m. to 5 p.m. weekends. Admission is free. Visitors can wander at will, and all the plants are labeled. The garden staff is gradually changing to a new labeling system that provides more information about each plant and its relationship to the human race.
People, and how they fit plants into their lives, are what define this garden. The size and scope of the National Herb Garden make this point vividly for the first-timer visitor. As Holly Shimizu puts it: “People walk in thinking herbs are simply parsley, chives, maybe dill. They can’t believe it. ‘Do you mean that this entire garden is made up of herbs?’ That’s the most important message for people—what a vast group of plants this is and how important they are to humankind, to the world, and to their own lives. It changes perceptions about what an herb is.”
Kathleen Halloran, a veteran journalist living in Laporte, Colorado, is now assistant editor of The Herb Companion.