Astilbe × arendsii 'Irrlicht'
Common Name: astilbe
Type: Herbaceous perennial
Family: Saxifragaceae
Zone: 3 to 8
Height: 1.50 to 2.00 feet
Spread: 1.00 to 1.50 feet
Bloom Time: May to July
Bloom Description: White
Sun: Part shade to full shade
Water: Medium
Maintenance: Low
Flower: Showy
Tolerate: Rabbit, Deer, Heavy Shade, Black Walnut

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

Arendsii hybrids are a large group of hybrids involving crosses between A. chinensis, A. japonica, A. thunbergii and A. astilboides and named after German nursery man George Arends (1862-1952). They are clump-forming perennials which feature graceful, fern-like mounds of mostly basal, 2-3 ternately compound leaves, usually with sharply-toothed leaflets, and tiny flowers densely packed into erect to arching, plume-like flower panicles rising above the foliage on slender, upright stems. They can vary considerably as to plant size, inflorescence shape, leaf color/shape and bloom period because of the different and sometimes complex parentage of the various plants now lumped under this hybrid grouping.

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 honors German nursery man George Arends (1862-1952)

'Irrlicht' is a white-flowered cultivar that typically grows to 24" tall and to 18" wide. It features an attractive foliage mound of compound, dark green leaves (each to 15" tall) with sharply-toothed leaflets. Tiny, slightly fragrant, white flowers in airy, erect to arching, densely packed branched panicles bloom above the foliage on slender, upright stems from late spring to mid-summer (May-July).

Problems

No serious insect or disease problems. Foliage decline (leaves brown up) may occur in hot summers and/or periods of drought if soils are not kept moist. Powdery mildew and wilt may appear. Japanese beetles may chew on the foliage.

Garden Uses

Mass or group in shade gardens, woodland gardens and shaded areas of border fronts and cottage gardens. Excellent ground cover or edging plant for shady areas. Also effective on pond or stream banks. Foundations.