Actaea biternata

Actaea biternata, sometimes called Cimicifuga japonica var. biternata, is a botanical bugbane, quite rare in cultivation, which easily adapts to shady areas of the garden, even hot climates if the soil remains moist. It is a beautiful perennial, elegant in shape, luxuriant in its foliage, and charming in its luminous flowering at the end of summer with tall and graceful white spikes tinged with pink. Vigorous and hardy, this plant establishes slowly, but then lasts for years. Give it a good spot at the back of a semi-shaded, or slightly sunny bed.

Actaea biternata is a plant of the buttercup family native to Japan (Honshu) and South Korea. In the wild, it is found in high-altitude forests. It is a perennial herbaceous plant that loses its above-ground vegetation in winter. Growing from a crown with fibrous roots arranged in compact masses, this plant slowly forms bushy clumps with foliage reaching 60 cm (24in) high, and sometimes up to 1.25 m (4ft) in flower, with a minimum spread of 50 cm (20in). Its stems are covered with large, thick leaves divided twice into three toothed lobes, sometimes 50 cm (20in) long including the petiole. They are bright green, sometimes bordered with yellow. Flowering usually begins in August, in the form of numerous large unbranched terminal inflorescences forming slender spikes of white flowers tinged with pink, upright or slightly curved, with tiny stamened flowers with no fragrance. This flowering is very attractive to bees and nectar-loving insects. The species name of this plant, biternata, refers to the way the leaves are divided: twice divided into 3 parts.

Actaea biternata will thrive in semi-shade, in the dappled light of a clear woodland or at the edge of a forest, but this species can also tolerate some sun. It tolerates competition from the roots of trees and bushes, as long as the soil does not dry out too much in summer. At the back of flower beds, its sculptural silhouette and luminous flowers will create a beautiful backdrop for perennials that have finished flowering at the end of summer. Whether placed as a specimen or in small groups of 3, a background of dark foliage (conifers, hollies, boxwoods, osmanthus) will enhance its flowers. For example, you can associate it with shade-loving perennial geraniums (Geranium nodosum, G. cantabrigiense, G. macrorrhizum...)