Epimedium

Bishop's Hat is a group of herbaceous rhizomatous perennials in the barberry family.  Commonly called Bishop's Hat or Barrenwort, the genus name is of unclear origin and meaning, however it has been suggested that the common name has been derived by the belief that the roots from the plant cause women to become barren. 

Most species are native to China but there are some that are native to the Mediterranean areas.  This plant has been cultivated and hybridized for over 150 years and includes up to 58 species.  It can be grown in many locations where other plants would not survive.  Deep shade and drought conditions are not an issue for established plants.  Its shallow roots can even compete with the roots from surrounding trees without suffering any consequences.  

The species has small, charming, four-pointed flowers that can come in shades of red, pink, white, and yellow, blooming between May and June. Although considered frost-tolerant, early blooms can be damaged by late frost.  Habits include mounding and spreading.  With some deciduous varieties, flowers can bloom before the foliage open in the spring.  In general, the Asian varieties are deciduous and the Mediterranean ones are evergreen to semi-evergreen. There are many hybrids and cultivars to choose from.

Division should be accomplished every 3 to 4 years to ensure that the plant maintains it vigor.

Most Epimediums prefer shade to part shade in moist but well-drained fertile soils. Use these plants as a ground cover in the shade or woodland garden. In northern areas, they can tolerate more sun but will need more water in the summer. Propagation is best done in late summer by division.

Insects, Diseases, and Other Plant Problems: No significant problems. Slugs, vine weevils and the mosaic virus can affect these plants. 

Additional Epimedium Images at Juniper Level Botanic Garden