Epimedium leptorrhizum
Common Name: bishop's hat
Type: Herbaceous perennial
Family: Berberidaceae
Native Range: China
Zone: 5 to 8
Height: 0.50 to 1.00 feet
Spread: 0.50 to 1.00 feet
Bloom Time: April to May
Bloom Description: White tinged with rose pink and lilac
Sun: Part shade to full shade
Water: Dry to medium
Maintenance: Low
Suggested Use: Ground Cover, Naturalize
Flower: Showy
Leaf: Evergreen
Other: Winter Interest
Tolerate: Rabbit, Deer, Drought, Heavy Shade, Erosion, Dry Soil, Shallow-Rocky Soil

Culture

Easily grown in average, acidic, dry to medium moisture, well-drained soils in part shade to full shade. Prefers loose, organically rich loams with consistent moisture in part shade (sun-dappled or morning sun). Foliage will usually burn in full afternoon sun. Tolerates full shade. Also tolerates drought and dry shade (rhizomes hold moisture) once established. Intolerant of alkaline soils. Clumps spread by long creeping rhizomes, and will form attractive colonies over time. Foliage is evergreen south of USDA Zone 7 but basically deciduous in the St. Louis area. As needed, cut back any remaining old foliage in late winter prior to the emergence of the new growth. Propagate by division in early spring or fall.

Noteworthy Characteristics

Epimedium leptorrhizum is a low-growing, evergreen, rhizomatous perennial that typically forms a wiry-stemmed foliage clump to 6-8" tall. It is native to forests and thickets in central and southern China (Guangxi, Guizhou, Hubei, Hunan and Sichuan Provinces). Large, showy, nodding, white tinged with rose-pink (sometimes with a hint of lilac) flowers (each to 2" across) bloom in spring (April-May) in few-flowered inflorescences (to 4-12 flowers per inflorescence) which rise to 12" tall above a showy mound of evergreen, deeply-veined, cordate-based, olive green leaves with chalky white undersides. Flowers may be the largest in size of the many species of epimedum. Leaves are basal and cauline. Each flowering stem bears one trifoliate leaf. Narrow, ovate, textured, deeply-veined, olive green leaflets (each to 4" long) have spiny marginal teeth, cordate bases, and acuminate tips. New leaves in spring emerge with reddish-bronze spotting, but mature to medium to dark olive green.

Genus name is of unclear origin and meaning but the Greeks used epimedion for a very different plant.

Specific epithet comes from the Greek words leptos meaning slender and rhiza meaning root in reference to the slender rhizomes of this plant.

Epimediums are commonly called bishop’s hat (four-spurred flowers of some species resemble a clergyman's biretta) or barrenwort (root extract was once believed to prevent female conception).

Problems

No serious insect or disease problems. Mosaic virus (transmitted by aphids) is the main disease problem.

Garden Uses

Ground cover or edger for shady areas. Mass in woodland gardens, wild gardens or naturalized areas. Also effective in partially shaded areas of rock gardens and border fronts. Grows well under trees. Edger for paths and walkways.