Astilbe is a genus of rhizomatous herbaceous perennial plants in the family Saxifragaceae (order Saxifragales), comprising around 18 to 28 accepted species depending on the taxonomic treatment. The genus is native to mountain ravines and woodland habitats across a broad range in Asia — from New Guinea, Java, Borneo, and the Philippines through Indochina, the Himalayas, China, Japan, and the Russian Far East — with one outlier lineage in the southeastern United States. Common names include false goat's beard and false spirea, both reflecting superficial resemblances to unrelated plants with similar plume-like inflorescences.
Plants are hardy herbaceous perennials that die back to the ground each winter and regrow from fleshy rhizomes in spring. The foliage is typically large, compound, and often described as fern-like, providing ornamental value even outside the flowering season. The flowers are minute but massed into dense, feathery panicles that may be erect or arching, in colours ranging from white and pale pink through deep red and purple depending on species and cultivar. Flowers of at least some species are fragrant. Astilbe is notably tolerant of shade and waterlogged soils, making it a popular choice for pond-side and woodland garden planting; it also performs well in clay soils where many ornamentals struggle.
The genus has a long history of horticultural development. Numerous hybrid cultivars have been raised, many tracing back to the work of German nurseryman Georg Arends in the early twentieth century. Notable species in cultivation include Astilbe × photeinophylla, Astilbe × amabilis, Astilbe microphylla, and Astilbe glaberrima. Three National Collections of Astilbe are maintained in the United Kingdom at Marwood Hill Gardens, Holehird Gardens, and RHS Garden Wisley. Some species, including Astilbe rivularis, have ethnobotanical use in traditional medicine in parts of Asia.
Etymology
The name Astilbe derives from the Greek a- (without) and stilbe (brightness or glitter), a reference to the individually inconspicuous flowers of the type species. Despite the modest individual blooms, the massed inflorescences are highly showy in cultivation.
Distribution
Astilbe species are native to mountain ravines and woodland habitats across Asia, ranging from New Guinea, Java, Borneo, and the Philippines through Indochina, the Himalayas, China, Japan, and the Russian Far East. One species, Astilbe biternata (Appalachian false goat's beard), is native to the southeastern United States, representing a disjunct North American lineage.
Cultivation
Astilbe are widely grown as garden perennials for their feathery flower plumes and handsome foliage. They thrive in partial to full shade and moist or waterlogged soils, making them particularly suited to pond-side and damp woodland plantings; they are also tolerant of heavy clay. Numerous hybrid cultivars have been developed, many originating with the German nurseryman Georg Arends in the early twentieth century. Three UK National Collections are held at Marwood Hill Gardens (North Devon), Holehird Gardens (Cumbria), and RHS Garden Wisley (Surrey, housing Arends cultivars).
