Astilbe plants (botanical name: astilbe) have long-blooming, plume-like flowers in soft shades of white, pink and red. The flowers are held on tall, stiff stalks, above the airy foliage. Astilbes are one of the easiest perennial flowers to grow.
Virtually pest free, they can light up the shade garden or soften a sunny spot, and, they are very low maintenance.
Astilbe plants are also known as false spiraea, false goat's beard and meadowsweet.
The Appearance of Astilbe Plants
Astilbe foliage tends to be basal, with deeply toothed leaflets of alternately compound leaves. Feathery plumes of flower clusters appear on tall stalks above the foliage. Astilbe flowers come in shades of creamy white, pink, lavender, and red, and stay in bloom several weeks, slowly fading in color as they dry.
There are several species and cultivars within the Astilbe genus, with variety in the flower plumes; some spikier or fluffier than other. Most of the popularly sold Astilbes are hybrids resulting from crosses among the species.
Features of Astilbe Plants
Astilbe plants are widely adaptable and are hardy from USDA Zones 4 through 8. In hot, dry climates, they need to be planted in the shade and/or given plenty of water.
They are also full sun/partial shade. Astilbe will bloom in shade, but the plants prefer some sunlight to achieve their full size. However, in hot weather and dry soils, their foliage will burn, so partial shade, plus plenty of water, is preferable.
Different varieties will bloom anywhere from mid-spring to late summer. If you plant different types of Astilbe, you can prolong the bloom almost all season. The plumes remain in flower for several weeks and continue to look good as they fade and dry on the plant. No deadheading is needed since they will not bloom again.
Suggested Astilbe Varieties to Grow
There are new varieties being introduced every year and recently they've begun breeding for darker foliage, too. Some established standards include:
- Astilbe arendsii/ Bridal Veil: Mid to late season bloomer with full white plumes
- Astilbe arendsii/ Fanal: blooms early with blood red flowers on bronze foliage
- Astilbe arendsii / Rheinland: Another early bloomer in a rich pink, very hardy
- Astilbe chinensis taquetii/ Purple Candles: Deep purple, chenille-like plumes
- Astilbe chinensis/ Visions in Red: Compact plant with bronze foliage and deep red flowers.
Design Ideas for Using Astilbe in Your Garden
Astilbe is valued for bringing great long-lasting color to partly sunny borders, where tall colorful flowers are few. In addition, Astilbe provides a nice textural contrast to plants with large, broad leaves like Heuchera, Hosta, and Ligularia. Astilbe can also be grown in containers.
Astilbe Growing Tips
Astilbe plants prefer a slightly rich, moist soil. The warmer the weather, the more moisture they need, especially in full sun. They also prefer a slightly acidic soil pH of around 6.0.
Astilbe seed is available, but it can be difficult to germinate. It's easiest to start with a plant or division. Even a small plant will quickly fill out and perform well in its first year.
You can plant in either spring or fall but try and avoid planting in the hottest part of summer. If you must plant then, keep the plant well watered until you see new growth emerging.
Caring for Your Astilbe Plants
Extremely little maintenance is required of Astilbe plants. The flower heads will dry on the plant and remain attractive for many months. The flowers can be cut whenever they start to look ragged or left up, for winter interest, and cut back in the spring.
The biggest need Astilbe plants have is some relief from hot, dry weather. Either provide afternoon shade or extra water. They do not handle prolonged periods of drought well; the leaves will brown and dry and if left dry too long, the plants will die.
Divide every 4 to 5 years, to keep the plants healthy. Astilbe plants can grow quickly if they are given ideal conditions. More frequent division may be necessary. Keep the plants well watered after replanting and they will re-establish themselves quickly.
Pests and Problems of Astilbe Plants
Astilbes are virtually trouble free, bothered by few diseases or insects. The tender, new growth may be nibbled on by groundhogs or rabbits, but once the plants have filled out, the plants typically don't suffer any long-term damage.