Astilbes have pink, white, red, or purple plume-shaped blooms and finely divided foliage that's often shaded reddish or bronze. Once the flowers fade, you can dry the light-colored heads and use them in flower arrangements.
- Common name: Astilbe
- Botanical name: Astilbe spp.
- Zones: 4 to 9, depending on species
- Size: To 5 feet, depending on species
- From: Areas of Asia
- Family: Saxifragaceae (saxifrage family)
- Sun: Partial shade is best; the plants can grow in relatively sunny spots if the soil remains moist.
- Soil: Moist soils rich in organic matter are best.
- Moisture: Keep soil moist at all times. Astilbes like moisture and can even grow in bog and streamside gardens.
- Mulch: A 2- to 3-inch layer of mulch around the plants will help conserve moisture and prevent the soil temperature from rising too rapidly, especially in warm-summer areas.
- Pruning: Cut down dead stalks in autumn after they freeze or in early spring before the plants begin to grow.
- Fertilizer: In soils rich in organic matter, extra fertilizer isn't necessary. In other soils, use a general-purpose fertilizer in spring.
- Division: Division is best in spring or autumn, though it can be done any time.
- Leaf spot: In summer or autumn, the leaves develop yellow or dark-colored spots with concentric rings around them, forming a bull's-eye pattern. To deter it, prune the plant to maintain good air flow, and avoid wetting the foliage in afternoons and evenings.
- Powdery mildew: This disease appears in mid- to late summer. Affected leaves develop a gray powdery covering and drop off. To deter the disease, prune the plant to allow good air flow and avoid wetting the foliage in afternoons and evenings.
- Slugs/Snails: Slugs and snails chew leaves at night. To deter them, surround plants with a ring of horticultural-grade diatomaceous earth. Some people lay copper strips around plants, but this not always successful. If slugs are not particularly numerous, set out shallow containers of stale beer at ground level. Slugs are attracted to beer; they will crawl into it and drown.
- Astilbe ‘Deutschland': A well-known white-flowering astilbe that grows 2 feet tall with green foliage. It blooms early in the season. Zones 4 to 9.
- Astilbe ‘Fanal': A red-flowering cultivar that grows 2 feet tall with bronze-shaded foliage. Early-season bloomer. Zones 4 to 9.
- Astilbe ‘Federsee': A rose-flowering cultivar that grows 2 feet tall with bronze-shaded foliage. Midseason bloomer. Zones 4 to 9.
- Astilbe‘Purple Candles': It grows 3 feet tall with red-purple plumes. Late-season bloomer. Zones 4 to 9.
- Astilbe‘Rheinland': A pink-flowering astilbe that grows 2 feet with green foliage. Early-season bloomer. Zones 4 to 8.
- Astilbe ‘Sprite': Arching, light pink blooms on 1-foot-tall plants. Perennial Plant of the Year winner. Zones 4 to 8.
- Astilbe thunbergii ‘Ostrich Plume': Salmon pink blooms with a pendulous form. Large plants grow to 4 feet tall. Zones 4 to 8.