By Adrian Higgins
Thursday, April 24, 2008
One minute the emerging hostas are three-inch horns, the next they are pumped up like a newly minted butterfly. This is the nature of late April. Blink and you miss it.
One plant not to be missed is the trillium, now in full glory on the woodland floor. A fleeting wildflower, the trillium is big on threes, hence its name. Most of its parts form botanical trios: three leaves, three sepals, three petals. Look hard enough and you will find three stigma surrounded by, all right, six anthers.
As with other wildflowers of the moment -- slipper orchids and Virginia bluebells, for example -- the trillium holds a mystique in our part of the world. It was an important herb for American Indians and colonists and signified the arrival of spring. The classic Trillium grandiflorum is also called the large-flowered wake-robin because it would emerge as the robins flocked. Jeanne Frett, a research horticulturist and trillium expert, finds her own threesome (of words) to describe trilliums: "Magical, ethereal, coveted."
I met Frett last week at the Mount Cuba Center, where she and other horticulturists grow and study native flora at the 650-acre estate of the late Pamela du Pont Copeland north of Wilmington, Del.
"Everyone knows what a trillium is, but not many people have them in their gardens," she said. Copeland had an abiding interest in trilliums and made sure her shaded garden was full of these spring beauties. The deciduous forests of the eastern United States are the most trillium-rich habitat in the world. Of the 48 known species worldwide, 35 are North American. Copeland and her staff amassed an impressive 24 species at Mount Cuba. You can see them for yourself this weekend, when the center holds its annual open house.
There are two essential trillium experiences. The first is to discover an established natural stand in the woods. I know of a streamside glade near Staunton, Va., sprinkled with hundreds of wake-robins. As the flowers age, they turn from creamy white to pink to lavender, so the effect is of a kaleidoscope. The other is as a lone specimen in the garden -- lone, because trilliums are expensive: Ethically propagated plants are about $20 a pop because they are seed grown and take two seasons to germinate and five to seven years to reach blooming size.
"Some are sold as 'nursery grown,' " Frett said. That sounds ethical, but the plants have been potted from wild collected rhizomes. "You have to be careful about the terminology," she said. " 'Nursery propagated' is what you want." And trilliums for sale on eBay probably haven't been raised lovingly from seed sown in 2001.
The experience at Mount Cuba suggests how, with time, patience and some TLC (money, too), you can amass enough trilliums in a garden setting to suggest the beauty of a decades-old natural colony. The horticulturists grew 1,000 large-flowered wake-robins to blooming size from seed collected, with permission, from wild populations in Virginia.
It helps, of course, that the woods at Mount Cuba provide perfect trillium conditions: clay enriched with leaf mold and the high, dappled shade provided by the tall canopy of mature tulip poplars.
Walking this woods path with gardener Gregg Tepper, I stop to consider the aptly named little trillium, just six inches tall or so and with delicate, wavy-edged flowers that start white but age to rose. "It's been very easy, very successful," he said.
"This is another easy one to divide," he said, pointing to the twisted trillium, named for the way its maroon petals corkscrew. The sepals behind them are green but with a maroon base and the slightest fine edge, again in maroon, that rewards the close observer.
Nearby, a double-flowered bloodroot is in full bloom, as are the Virginia bluebells.
The easiest trillium for the home gardener, Tepper said, is the large toadshade ( T. cuneatum), named for the mottling patterns of its broad leaves. Unlike a lot of trilliums, it will take dry shade conditions. This spreads in time but does so as individuals, not clumping like the large-flowered wake-robin or the little trillium ( T. pusillum). "But I'm really fond of cuneatums, and they are so early," Tepper said.
One of my favorites is the yellow trillium ( T. luteum), whose yellow-green blossoms exude a lemon scent. In the woods around the ornamental ponds at Mount Cuba, Tepper showed me one of the most beautiful of all trilliums, the deceiving toadshade ( T. decipiens). Its deception is in resembling the taller T. underwoodii. Both have striking mottled leaves with a silver band along the midrib of the leaf. The flowers are a pretty maroon but secondary to the leaf ornament.
Once established and happy, trilliums are much tougher than they look. Tepper even divides them in bloom. "As long as they are dug, divided and replanted within half an hour, they wouldn't miss a beat. Do it on a misty day, or when it's overcast."
Two other native species can ruin your trillium collection. White-tailed deer love the top growth; voles devour the roots. The latter pest can be controlled by surrounding the rhizomes in grit. Deer must be fenced out.
To overcome the disparity between supply and demand for these spring beauties, scientists at the University of Delaware and the Atlanta Botanical Garden have succeeded in propagating some species of trillium by tissue culture. This would speed nursery production, even if each would be a clone of its parent. This would take away from the endearing variation found in trillium seedlings, in their marking and coloration and size.
"You get a lot of variation in seedlings," Frett said. "There are also a lot of dogs, too. They combine the worst characteristics of the plants."
Happily, they haven't seemed to have made it in the woodland garden.
Mount Cuba Center's fourth annual wildflower celebration is Sunday from 10 a.m. to 4 p.m. This is the garden's annual open house, and it's free. It coincides with peak bloom of trilliums and other spring ephemerals. For details: 302-239-4244 orhttp://www.mtcubacenter.org.