The Latest Export From China -- Garden Plants

The opening of China to the West in the past two deacades may prove to be a continued boon to gardeners in the United States, with the introduction of exciting new garden plants from one of the richest horticultural regions in the world.

For more than a century, Western plant collectors have coveted China's flora, and through their exploits they changed the face of our landscapes with beautiful plants, such things as Asian species of maples, hollies, barberries, liriope, viburnums, lilies and primroses, to name a few.

Sharing similar latitudes and temperate growing environments as the United States, China nevertheless has twice as many native plants (three times that of Europe). Glaciers and a deep freeze destroyed much of the primal flora of Europe and North America in the last Ice Age, but they left China relatively unscathed, says Douglas Justice, curator of collections at the University of British Columbia's Botanical Garden in Vancouver.

He is among a number of North American plant collectors who in recent years have brought back new or forgotten plants for study and use here, treading in the footsteps of previous Western explorers who risked life and limb in their quests.

How much is still to be discovered in China's four main physical regions remains open to debate. One modern-day plant collector, Barry Yinger, of Lewisberry, Pa., says that in China's southern fringe with Vietnam, Laos and Burma "no one has looked at the flora in a systematic way. You're in the richest floristic region in the world -- it's only fair to think you're going to have opportunities to find many new wonderful garden plants."

And yet, there are signs that China's window once more may be closing. Several provincial governments are no longer permitting commercial collecting, and separately, the Department of Agriculture is now enforcing the need for importers to produce certificates of plant health from places that have no bureaucracy to issue them, according to Yinger and another leading Asian-plant collector and nurseryman, Dan Hinkley.

The new trove, then, may already be here, ready to try. At the Botanical Garden in Vancouver, a good number of them have been planted at the 35-acre David C. Lam display garden, including hardy perennials, shrubs and trees, collected in the past 15 years or brought here earlier but still unknown to the gardening public.

Justice and two colleagues -- Peter Wharton and Brent Hine -- have written a new book showcasing these plants: "The Jade Garden" (Timber Press, $34.95).

Among the perennials featured are two odd, climbing versions of monkshood. They resemble small, flowering clematis in their desire to scramble through supporting shrubs. The monkshood, smothered in blue flowers, would work in partial shade.

A plant named Ellisiophyllum pinnatum may be in need of a catchy common name but it stands to expand the limited choices of perennial ground covers for shade, being an alternative, perhaps, to pachysandra, English ivy, liriope or vinca. Hine, describing it in the book, said: "It creates a wealth of small and sparkling, pure white, five-petaled flowers with yellow eyes, offered over an extremely long season."

Among shrubs featured in the book is a plant related to our common summersweet. It is called Clethra delavayi , first collected in western Yunnan in 1913, and grows into a large shrub with striking white blossoms in summer. It is a mountain plant that may not like Washington's muggy summer nights, but it would be fun to put it to the test.

Wharton also introduces the reader to three new varieties of cotoneaster, a beautiful pendant shrub that can be tested in our heat. One named Cotoneaster glabratus has evergreen leaves that complement "purplish maroon shoots and stems that are maintained throughout the hottest summers."