Family: Ranunculaceae
Common Name: Bugbane

Allegedly used in Europe to eradicate bed bugs, these hardy, herbaceous, northern hemisphere perennials usually grow 1-2 m (3-6 ft) in height and work well at the hack of a border. They have large, compound leaves and spikes of small white flowers. They are thought to be an effective insect repellent.

Species

C. americana grows 1-1.5 m (3-5 ft) tall and produces creamy white flowers in summer.

C. racemosa, black cohosh or black snakeroot, grows 2-3 m (6-10 ft), with broad spikes of white flowers.

C. rubifolia has large, heart-shaped leaves at the base and grows to 2 m (6 ft).

C. simplex, from Russia, China and Japan, is a clump-forming perennial which grows to over 1 m (3 ft). Spikes of white flowers are borne in early to mid-tall. Cultivars include 'Brunette' which has dark, purple-brown foliage.

Cultivation

These plants need a lot of moisture. Propagate from seeds sown 6 mm (¼ in) deep in boxes in autumn or by division of the roots in spring.

Climate

Zone 5 for most species.