You'll never fall in love at first sight with Epimedium the way you might swoon over roses or peonies. But once you get to know this genus—and appreciate its reliability, durability, and sophisticated good looks—I guarantee you'll enjoy a long-lasting relationship. For my part, I have always counted on a few Epimedium species for evergreen groundcover in dry shade and as part of the textural tapestry of the woodland floor. However, after hearing a talk by plant hunter and hybridizer Darrell R. Probst at the Vancouver Hardy Plant Group's Study Weekend, in June 2005, serious craving and collecting urges kicked in. Grower and hybridizer Diana Reeck (of Collector's Nursery fame) also stoked the flames of my Epimedium fever.
A member of the Berberidaceae, or barberry family, Epimedium is commonly called barrenwort or bishop's hat. It has the same tough and sturdy nature as its kin—Mahonia, Berberis, and Vancouveria are all in the same tribe. Native to woodlands and shady, rocky places from the eastern Mediterranean to eastern Asia, Epimedium species have recently been introduced in large numbers to the West, thanks to the work of intrepid explorers like Probst, Dan Hinkley, and their helpful guides.
A perfect groundcover for moist or dry shade, bishop's hat typically produces oval, heart-shaped, or shield-shaped leaflets in groups of 3 to 50. Wiry stems give the plant a buoyant personality and allow autumn leaves and needles to fall through and mulch the ground below. Underground rhizomes hold moisture and enable the plants to tolerate dry shade, although they perform best in well-draining, moist soil. Most species in cultivation are hardy from USDA Zones 5 to 9.
Quite a few Epimedium species and cultivars are evergreen, and many are tinted red in spring and bronze in fall and winter. Sprays of white, yellow, pink, orange, or lavender flowers appear in spring. Some Epimedium blossoms look like miniature columbines or tiny daffodils, while others appear more like spiders or stars. Species with long sprays can even resemble orchids.
If you become seriously interested in bishop's hat, William T. Stearn's The Genus Epimedium (Timber Press, 2002) is a must. Scholarly and thorough, it offers a comprehensive study of the plants, accompanied by helpful illustrations and photographs. The seven-page bibliography will catapult you further into Epimedium territory.
Time-Tested Evergreen Forms
One of the most vigorous and reliable cultivars—landscapers count on it for its sturdiness and availability—is Epimedium × versicolor 'Sulphureum', with yellow flowers and evergreen leaves. It stands about a foot tall and is very drought tolerant. The related cultivar 'Neosulphureum' has lighter yellow flowers that up close look like tiny daffodils.
Epimedium × perralchicum 'Frohnleiten' is equally tough and even showier. New leaves in spring are flushed red, with a dramatic pattern of bright green veins. The flowers are a vibrant bright yellow. My colony of 'Frohnleiten' thrives in dry shade at the base of a fruiting plum tree, and it fills in quickly whenever I take occasional divisions to transplant to other shady beds begging for color. Slower to develop but worth the wait, Epimedium × rubrum has small red flowers with white spurs that add sparkle to the plant. The foliage flushes red in spring and turns bronze in fall. The newer hybrid 'Sweetheart' offers larger, darker green foliage, heavily flushed with red in spring. Flowers are also larger and brighter pink.
For the Flowers
Profuse displays of medium to large flowers make Epimedium grandiflorum very appealing, even though the species is deciduous in climates colder than Zone 7. The cultivar 'Lilafee' illuminates shady places with plentiful lilac flowers above leaves tinted with purple. 'Rose Queen' sends pink flowers up above leaves flushed with bronze, and 'Purple Prince' offers irresistibly rich deep purple flowers.
Epimedium grandiflorum var. higoense 'Bandit' offers the best of both worlds—exquisite foliage and superb flowers. Each heart-shaped leaf is outlined in dark purple; then in spring, large white blossoms hover above the foliage and add dramatic contrast to the show.
Epimedium rhizomatosum offers the longest bloom period of the genus, beginning in spring and continuing as late as September. Long flower stems arch out, bearing spiderlike, clear yellow flowers with tiny red sepals. The evergreen leaves have red markings in spring.
Hailing from the Wushan Mountains in China, Epimedium wushanense (fairy wings) is distinguished by two-foot-long arching flower spikes, each holding up to a hundred flowers. The flowers are more than an inch wide, with yellow centers and white spurs. The elegant dark green leaves are equally arresting—long and narrow, with spiny edges.
If you're craving orange flowers, you will want to grow Epimedium × warleyense, which produces evergreen leaves topped by flowers of crimson and yellow, which translate as orange to the eye. The cultivar 'Orangekönigin' is a lighter shade of orange, more of a tangerine, with dark orange veins, and it forms a denser clump than the straight hybrid.
Tall sprays of small creamy-yellow flowers, rising up to two feet above the foliage, may fool you into thinking you are looking at a Heuchera or Saxifraga, but it's actually Epimedium pubigerum. This drought-tolerant species' evergreen leaves are small, heart-shaped, and leathery and have a tint of purple in the spring.
Named in honor of the late Harold Epstein, a remarkable plantsman who embraced Epimedium before it became popular, Epimedium epsteinii has beautiful bicolored flowers of pure white and reddish purple. Anywhere from 10 to 30 flowers bloom on each stem above glossy, dark evergreen leaves.
Compatible Companions
I love combining this genus with Helleborus × hybridus cultivars for the contrast between the heart-shaped Epimedium foliage and the hand-shaped leaves of the hellebores. Moreover, hellebores start their bloom cycle in early winter, and Epimedium follows them with flowers in spring, so that the color keeps coming in a continuous stream. An edging of Pulmonaria, especially varieties with blue or white flowers, adds a complementary ribbon of color and contrasting tapered leaves. Drifts of yellow 'Tête-à-tête' or 'February Gold' daffodils planted amid the Epimedium add another level of complexity to the early-season palette.
For additional spring color, plant white trilliums (Trillium grandiflorum) and pink glacier lilies (Erythronium revolutum). To fill in any gaps while Epimedium plants are growing up, I like to use columbines (Aquilegia species) and—despite the fact that it self-sows wildly—Viola labradorica, which has lovely near-black purple leaves and purple flowers.
For contrasting texture, ferns make wonderful partners—their lacy fronds arising like feathery plumes behind the more solid Epimedium foliage. Heuchera species and varieties, with their maple-shaped leaves, are also captivating companions, especially because they provide such a range of foliage colors. Try lively 'Plum Pudding,' with its tints of silver, pink, and wine; luscious 'Chocolate Ruffles', cocoa-brown on top and burgundy underneath; and handsome 'Green Spice,' with its red-veined silver-green leaves.
For summer color, hardy geraniums (Geranium species) marry well with Epimedium, especially clump-forming ones that don't spread aggressively, like the new blue-violet hybrid ROZANNE. Cultivars of toad lily (Tricyrtis species), with their weirdly wonderful flowers, are welcome for late summer. To extend color into fall and add height, plant some yellow wax bells (Kirengeshoma palmata), with their handsome maplelike leaves and small tubular yellow flowers.
Culture and Care
With little vulnerability to pests or diseases, Epimedium species are among the easiest plants to grow. Occasional plants infected by viruses should be discarded—symptoms include patterns of yellow or cream on the leaves. If plants are grown in extremely soggy soil, they may be vulnerable to root weevils.
Ideally, Epimedium species should be grown in conditions mimicking their native woodland habitats, where they're naturally mulched by fallen leaves. In gardens, they thrive in well-drained yet moist, fertile soil, in dappled shade or morning sun. Strong afternoon sun will most likely burn their leaves, and summer drought or strong winds will burn their rhizomes—so avoid planting where these conditions can occur. In spring, Epimedium plants will benefit from some slow-release fertilizer, followed by a generous layer of mulch over the rhizomes.
I like to cut back the old leaves of evergreen cultivars in early winter so that the flowers will bloom without the distraction of tattered foliage. Make sure to do this before the flowering stems rise up, or you risk cutting off new flowers along with old leaves. If you skip this step, new leaves will arise above the old ones, creating a taller plant.
To propagate Epimedium, lift clumps in early spring or early fall and divide them with a sharp knife. Replant each division in well-draining soil amended with compost, and keep them moist while they settle in.
Nursery Sources
Forestfarm990 Tetherow Road
Williams, OR 97544-9599
541-846-7269
www.forestfarm.com Garden Vision (run by Darrell Probst)
63 Williamsville Road
Hubbardston, MA 01452
978-928-4808
www.home.earthlink.net/~darrellpro/ Naylor Creek Nursery
2610 West Valley Road
Chimacum, WA 98325
360-732-49832
www.naylorcreek.com
