If visions of fairy-tale gardens surrounding your castle swim in your head, astilbe is the flower for you. This feathery flower appears to float above the ground, giving the illusion of sweet cotton candy amid the shadows. Tucked into shady corners or near a garden bench, it the creates a magical atmosphere that invites weary gardeners to seek rest and relaxation. This easy-to-care-for plant blooms profusely from spring to late summer.
Select an area for astilbe that receives full sun to partial shade and till the soil to a depth of 8 inches. Remove rocks, roots and other debris from the soil and rake smooth.
Spread a 2- to 3-inch layer of compost or well-rotted manure over the soil and work in well to improve drainage and aeration and provide a source of slow-release nutrients. Astilbe prefers moist, sandy soil but thrives in any humus-rich soil that drains well.
Dig a hole in the prepared soil that is twice as big as the root ball of your astilbe seedlings and plant to the original planting depth. Fill in around the roots with soil and firm down to secure the seedlings in place.
Space individual plants 12 to 14 inches apart, depending on the height of the cultivar at maturity. Astilbe ranges in height from 1 1/2 to 4 1/2 feet with typical varieties reaching 2 to 3 feet in height. Check the plant identification tag for recommended spacing.
Plant in groups of three or five plants to create a cloud of rich color that looks like it sprang from nature.
Water deeply once a week to moisten the soil to the root level. Monitor soil for signs of drying during hot dry periods, as supplemental water may be required for these moisture-loving plants.
Apply water-soluble fertilizer every two weeks. Follow the recommended application rate on the container.
Cut back foliage to ground level in late fall after a killing frost. Mulch lightly with 2 to 3 inches of leaves or other organic mulch to protect roots from harsh winter weather. Remove mulch in spring when new growth appears.