Growing an Heirloom

Cardoon was a staple in colonial gardens. A dead ringer for globe artichoke, the cardoon's leaves--not its heart--was eaten. Tennis-ball lettuce--a plant that Thomas Jefferson once grew--forms a small, loose, light green head. The scarlet runner bean is a twining vine with bright red flowers and edible pods. The balsam apple (Momordica balsamina) produces bright-orange fruits (or "apples") that split apart when ripe, exposing red seeds. Jefferson planted this annual vine, which was used to treat wounds, in his flower border.

A couple of hundred years ago Thomas Jefferson could step into his garden at Monticello and pick Prussian blue peas, Chili strawberries and blackberry lilies. At Mount Vernon on the Potomac River, George Washington grew at least four varieties of apples. Thanks to friends and neighbors who regularly shared seeds and cuttings, he enjoyed Persian jasmine and cranberrybush viburnum. Down in Colonial Wiliamsburg settlers ate home- grown skirrets and cardoon and cultivated germander for its reported effectiveness in curing gout and urinary-tract infections.

Today in your garden, if you had a mind to, you could nurture the direct descendants of many of these same vegetables, fruits, herbs and flowers. You could tend the same speckled beans, red-throated morning glories and kiss-me-over the-garden-gates that were beloved by 19th-century grandmothers. You cannot, however, grow sugarloaf cabbage or the marrowfat pea--just two of the thousands of plant varieties that have disappeared over the centuries.

These days 90 percent of the world's food supply comes from just 20 species. Scientists fear that when a new pest threatens a species, an heirloom variety that could have been resistant may already have disappeared.

But the threat of extinction isn't the only force driving the small horde of seed savers who have made heirlom varieties--those handed down through families over generations--such a hot item in contemporary gardens. Sometimes it's the quest for superior flavor or fragrance or a yearning for a direct link to the past. And sometimes it's simply the urge to find a good variety and not be forced to buy seed every year.

Heirloom varieties bear seeds that remain true to the parents. For these open-pollinated plants, seeds collected even several generations later produce offspring that exhibit essentially the same characteristics as the originals. The same cannot be said of the seeds of hybrids, which produce markedly different--and usually inferior--plants. Because of hybridization, many varieties have become high-performance items, with greater ranges of height and color, improved pest resistance and vigor and larger fruits that can tolerate cross-country shipping.

But traits that commercial producers prize, such as thick skins on tomatoes, may be the last thing a gardener wants, says Diane Whealy, co-founder of the Seed Savers Exchange, a non-profit organization whose 7,000 members save and exchange heirloom seeds. "When you breed for characteristics other than flavor, you lose that trait," she notes.

Heirloom enthusiasts swear their tomatoes are far more flavorful than hybrids, and theirs also come in yellow, orange, pink, black and striped varieties. Talk about diversity.

In Jefferson's garden it wasn't unusual to spot a half-dozen kinds of peas. Over the decades, he experimented with 250 varieties of more than 70 vegetable species. Also an avid gardener, Washington received seeds, cuttings and bulbs from all over the world. One such shipment came from the botanist to King Louis XVI of France, another from China. In Williamsburg 150 species of flowers and herbs were cultivated.

Are heirlooms really better--more flavorful, more pest and disease resistant, more fragrant? Often yes, sometimes no. True, open pollination and either natural or purposeful selection mean that only the fittest and best survive. The roses of old often bear a fragrance that most modern hybrid teas can only dream of. A sunflower variety grown by the Havasupai tribe in the Grand Canyon turned out to be one of just a few in the world that can resist a fatal rust fungus.

What about those skirrets and cardoons? Cardoon is a dead ringer for globe artichoke, except that the leaves are eaten, not the heart. Skirrets are a parsniplike vegetable with pencil-shaped roots that bear a woody, stringy core.

And the colonists never enjoyed sugar snap peas or dwarf marigolds: those are hybrids--gifts of a later day.

Jefferson's Favorites

The statesman who ranked his introduction of the olive tree and dry rice into South Carolina as two of his top lifetime achievements, Thomas Jefferson was first and foremost a gardener. "The greatest service which can be rendered any country," he wrote, "is to add a useful plant to its culture."

Jefferson kept meticulous records on each variety's performance. He delighted in serving his guests tomatoes, at that time still widely considered poisonous. And each spring he competed with his neighbors to see who could get the first English pea to table.

Photography, courtesy of the Thomas Jefferson Center for Historic Plants