Astilbes: Plant Care and Collection of Varieties
Astilbe produces an attractive mound of glossy, fernlike foliage topped with delicate plumes of colorful flowers. Another common name is false goat’s beard.
Astilbe does best in regions with cool, moist summers. The large plumes of frothy flowers arrive in late spring or early summer to brighten shade gardens. Flower colors include pink, red, lavender, and white. The plant grows between 6 inches and 5 feet tall, depending on the variety. Use in woodland gardens and along waterways with other shade-loving perennials, such as hostas and ferns.
Special features of astilbes
Easy care/low maintenance
Tolerates wet soil
Choosing a site to grow astilbes
Select a site with light to full shade and moist, humus-rich soil. Astilbes may tolerate full sun as long as soil remains consistently moist.
Plant in spring or fall, spacing plants 1 to 3 feet apart, depending on the variety. Prepare the garden bed by using a garden fork or tiller to loosen the soil to a depth of 12 to 15 inches, then mix in a 2- to 4-inch layer of compost. Dig a hole twice the diameter of the pot the plant is in. Carefully remove the plant from its container and place it in the hole so the top of the root ball is level with the soil surface. Carefully fill in around the root ball and firm the soil gently. Water thoroughly. If planting bare-root plants, dig a hole twice as wide as your plants and 4 to 6 inches deep. Position the fibrous roots in the hole so that the crown is 1 to 2 inches below ground level. Cover with soil and press firmly.
Apply a thin layer of compost each spring, followed by a 2-inch layer of mulch to retain moisture and control weeds. Water plants during the summer if rainfall is less than 1 inch per week. Astilbes multiply rapidly. Divide plants every 3 to 4 years as new growth begins in the spring, lifting plants and dividing them into clumps.
Astilbe Planting Guide
Gardeners with lots of shade discover early on that the list of visually impactful options is limited. Allow us to introduce astilbes, your new friend. These plants thrive as foundation color on the north (shady) side of your house or garage, or under the canopies of deciduous trees. Astilbes also provide fluffy filler color for flower arrangements, material you’re unlikely to find at any floral supply shop. As a bonus, astilbe flowers also attract butterflies and support pollinators like honeybees.
Choosing a Site for Astilbes
Astilbes prefer some shade and are happy with a range of light from dabbled sunlight to moderately shady to the shade that’s found on the north side of buildings. (Sorry, nothing’s going to grow robustly in the dense dark shade under that giant blue spruce.) Astilbes are more tolerant of clay soils than are most perennials plants.
Light to moderate feeders, astilbes grow well in average, well-drained soil and don’t require rich, perfect loam. Compost, dug in when planting or added as a top dressing later, provides a welcome supply of nutrients.
When to Plant
Plant outdoors when frost danger has past. Astilbes are hardy perennials and can take freezing without ill effects once they are established. For fall planting, get your astilbes in the ground at least 6 weeks before hard frosts typically arrive in your region. This gives the plants time to develop sufficient roots before going into winter.
How to Plant Dormant Bareroot Astilbes
Your astilbes will be shipped bareroot, in a dormant state. Dormancy means the plant is not in actively growing; it’s been held in a cool, dark setting similar to winter garden conditions and is “sleeping”. The bareroot term means that the soil has been washed from the roots; there is no risk of introducing any soil-borne diseases into your garden, and the plants are lighter and cleaner to ship. When you plant your astilbe, adding light and moisture, they’ll wake up. Roots will start growing in a few days and top growth will be visible in 1-3 weeks. Fall planted astilbes will develop roots in the cool, but not frozen, soil and sprout top growth in spring.
Dig a hole a bit bigger than the root ball and mix in a couple scoops of compost. Fan out the roots in your planting hole and place the crown (area from which leaves will sprout) an inch below soil level. Refill around plant with soil, tap down to eliminate any big air pockets and water well.
In the garden, space your plants so they have enough room to grow without crowding. Allow 18-24” between plants for full size astilbe and 14-18” for the more compact Younique astilbes.
During the Season
Astilbes require little care during the growing season. During their first season, while they are settling in, make sure they receive 1-2” of water, from rain or irrigation, per week. From their second season on, they’ll be fine with about the same or a little less. Feel free to snip flowers; this won’t hurt the plants. Or leave the flowers to develop into seed heads and cut these for fall arrangements.
- Deer and rabbits tend to avoid astilbes. If hungry deer and/or rabbits are a problem in your area, astilbes could be the perfect solution.
- Astilbes will tolerate soil that’s on the moist side. If part of your yard has less than perfect drainage and is shady, astilbes could be worth a try. Cool, moist summers are ideal for astilbes.
- Where happy, astilbes will readily grow into sizeable clumps. Divide every 3 to 4 years by lifting in the spring when you see new growth and pulling/cutting apart sections. Replant the new astilbes at soil level and water to settle in. Or share with friends!
How to Grow Astilbe
Growth Habit: Astilbe is a clump-forming perennial with fern-like leaves and tall flower stalks with plume-like flowers. Plants range in size from 1 to 4 feet tall. Astilbe looks best planted in groups and some low growing types make excellent ground covers. The brightly colored flowers last for a few weeks. Some gardeners will deadhead the flowers after this to keep the bed looking neat. But the flowers and seed heads maintain some of their color, even after drying on the plant, and can be attractive for a few months.
Staking: Because of their strong stems, astilbe usually don’t need staking. If tall varieties do flop in your garden, plants them closer together and in groups to support each other.
Watering: Astilbe needs to be watered deeply every week, especially during periods of dry, summer weather. If allowed to dry out, the foliage will brown and the plant may even die. However, astilbe doesn’t like soggy soils, so over watering should be avoided.
Fertilizing: Amend the soil at planting with compost. Each spring add a 1- to 2-inch thick layer of compost and a balanced organic fertilizer, such as 5-5-5, to help stimulate new growth and flowering. Side dress with another dose of organic fertilizer in early summer.
Trimming & Pruning: Although astilbe can be deadheaded after the flowers fade for a neater appearance, it isn’t essential. As with any herbaceous perennial, cut astilbe plants to the ground in fall to clean up the bed. This will reduce the number of diseases and overwintering insects.
If plants dry out and the foliage curls and browns during the summer, cut back the plant to the ground, water well and hopefully it will regrow to be attractive for the rest of the season.
Mulching: Astilbe benefits greatly from an organic bark mulch added each spring. Since astilbe does’t like to dry out, the mulch helps maintain soil moisture and adds organic matter over time to the soil. Mulch also prevents weed growth, allowing the plants to fill in quicker.
The Astilbe plant is a summer flowering perennial. Astilbes are also commonly called false spirea, feather flower, meadowsweet, and false goat’s beard. Astilbe plants can tolerate direct sun but it will perform best in partial or full shade. The astilbe plants prefer a location that is moist but not soggy.
Arguably, the astilbe is one of the most attractive of shade loving plants. Astilbe plants can display diverse foliage and flower colors. The foliage is very attractive and the plants add delightful color to a shade area even after the flowers are no longer blooming. Astilbes appeal to butterflies and also make very attractive dried flowers.
Astilbe is perfect for a rock garden, herbaceous border plant, or in containers. Container grown astilbe can be moved from sunny to shady garden locations to create color in areas that the sun no longer frequents as the seasons change. Astilbes plants range in height from 1 foot up to 4 feet tall. There are hundreds of cultivars now being produced that combine the feathery flower spikes with many foliage colors and flower color combinations.
Potted astilbes can be used as a house plant. If used in a house, the plant needs a well-lit location. If planted outside, too much exposure to the sun will shorten the flowering period. Astilbes can flower for 2 to 3 weeks if not over exposed to the sun. They require consistently moist soils; do not let them dry out between watering.
We offer several varieties of astilbes. Click the photos to learn more, or call our plant experts at (888) 864-7663.