Astilbe
false goat's beards
Eastern Asia and eastern North America
Overview
Astilbe spp. is a genus of about 18 to 25 species of rhizomatous perennials in the family Saxifragaceae, native to moist woodlands and stream banks of eastern Asia and North America. Plants form spreading clumps of compound, fern-like leaves divided into toothed leaflets, the foliage often bronze-tinged as it unfurls and deep green at maturity. Clumps reach 6-24 inches (15-60 cm) in leaf, and flowering stems rise well above to a total height of 1-5 feet (0.3-1.5 m) depending on species and cultivar. Tiny flowers are massed into branched, plume-like panicles in white, pink, red, lavender, and peach across the genus and its many hybrids. Bloom comes in early to midsummer and lasts two to four weeks; the dried flower plumes persist into winter. Garden plants come largely from A. chinensis, A. japonica, A. thunbergii, and A. x arendsii hybrids. The genus needs consistently moist soil and partial shade, and leaf edges scorch in dry or sunny sites. Most species are hardy in USDA zones 4 to 8 and benefit from division as clumps age.
Native Range
Astilbe spp. is native to eastern Asia, including China, Japan, and Korea, and to eastern North America, where A. biternata grows in southern Appalachian woods. Species occupy moist woodland, ravines, and stream banks. The greatest number of species occurs in eastern Asia.Suggested Uses
Astilbe spp. is planted in shaded borders, woodland gardens, and along ponds and streams for its foliage and summer plumes. Massed plantings cover ground in damp shade. The fresh and dried plumes are used in cut arrangements.How to Identify
Appearance
Size & Dimensions
Height1' - 5'
Width/Spread1' - 3'
Bloom Information
Most Astilbe spp. flower in early to midsummer, often June to July, with early and late cultivars stretching the season from late spring into August. Each plume lasts two to four weeks. The faded brown plumes hold their shape and stand into winter.
Detailed Descriptions
Flower Description
white, pink, red, lavender, or peachFoliage Description
green, bronze-tinged when youngGrowing Conditions
Sun Requirements
Requires 2-6 hours of direct sunlight daily
• Full Sun: 6+ hours of direct sunlight
• Partial Shade: 3-6 hours of direct sunlight
• Full Shade: Less than 3 hours of direct sunlight
Care & Maintenance
Care Guide
Astilbe spp. species grow in partial shade on consistently moist, fertile, humus-rich soil and tolerate full sun only where the soil stays wet. Soil pH near 5.5 to 6.5 suits most plants. Dry soil scorches the leaf margins and stunts the plumes, so even moisture is the main requirement. Plants are hardy in USDA zones 4 to 8 and spread slowly by rhizomes. Clumps lift toward the surface as they age and benefit from division every three to four years. Few pests trouble the genus, though dry wind and drought are the main limits.Pruning
Spent flower plumes can be left for winter structure or cut back in autumn. Cut old foliage to the ground in late winter before new shoots emerge. Lift and divide crowded clumps in early spring.Pruning Schedule
fallwinter
Container Growing
✓ Suitable for container growing
Minimum container size: 3 gallons