Valued for light, airy quality of plumelike flower clusters and attractive foliage and for ability to provide color from late spring through summer. Leaves are typically divided, with toothed or cut leaflets, though in some species they are simply lobed, with cut margins. Small white, pink, or red flowers are carried in graceful, branching, feathery plumes held on slender, wiry stems ranging from 6 in. to 3 ft. or taller. Most plants grow 2–3 ft.wide.
Astilbes are the mainstay of the shady perennial border, although in cool-summer climates they can withstand full sun if watered adequately. Effective at the edge of pools, along shady paths, in containers. Need moist (but not boggy), rich soil with ample humus. Cut off faded flowering stems and divide clumps every 4 or 5 years. Survival in coldest areas (Zones 1a, 1b, 2a) depends on good snow cover.
Grows to about 18 in. high and wide. Leaves are merely cut or lobed, not divided into leaflets. Better known than the species are it garden varieties and hybrids. ‘Pink Lightning’ has delicate blooms that emerge purplish red and open to clear pink. ‘Sprite’ (the best known) is a low-growing, compact plant that blooms profusely in summer, bearing drooping pink, 1-ft. spires above bronze-tinted foliage. ‘Hennie Graafland’ is similar but grows a few inches taller and blooms a little earlier.
This dwarf grows to 4–8 in. high, with two-toned flowers of white and blue, rose, or pink.
Bright pinkish purple flowers in spikelike clusters that grow to 4–5 ft. tall.
Grows to about 18 in. high and wide. Leaves are merely cut or lobed, not divided into leaflets. Better...