Culture
Easily grown in average, medium moisture, well-drained soils in part shade to full shade. Prefers moist, humusy, organically rich soils. Soils must not be allowed to dry out. If regularly watered, foliage will usually remain attractive throughout the growing season. A summer compost mulch helps retain soil moisture. Removing faded flower stalks will not prolong bloom but may improve plant appearance, particularly if a ground cover look is desired. On the other hand, many gardeners leave the flower stalks in place after bloom because of the continuing ornamental interest of the dried seed heads. Divide clumps when overcrowding occurs (every 3-4 years).
Noteworthy Characteristics
Astilbe simplicifolia is a dwarf species of astilbe that is native to Japan. As suggested by the specific epithet, the leaves are primarily simple, but sometimes appear in groups of three. This is a clump-forming perennial that features graceful, fern-like mounds (to 12" tall) of glossy, mostly basal, medium green leaves (to 3" long). Tiny white flowers in open panicles bloom in late spring to early summer atop slender upright stems rising above the foliage to 18" tall.
Species plants are infrequently sold in commerce, but a variety of named cultivars in the simplicifolia hybrid group are commonly available including 'Aphrodite' (salmon-red flowers), 'Bronze Elegance' (rose pink flowers), ‘Sprite’ (shell pink flowers) and 'White Sensation' (white flowers).
Genus name comes from the Greek words a meaning without and stilbe meaning brightness in reference to the dull leaves of some species.
Specific epithet means with simple entire leaves.
Problems
No serious insect or disease problems. Foliage decline (leaf margins brown up), sometimes with significant dieback, may occur in hot summers and/or periods of drought if soils are not kept moist. Powdery mildew and wilt are potential problems.
Uses
Astilbes are mainstays of shade and woodland gardens where they are effective in large groups or massed. Excellent ground cover or edging plant for shady areas. Also effective on border fronts, cottage gardens or pond/stream banks.