Preparing the Astilbe Bed

• Purchase astilbe in containers from your local garden center, or sow seeds indoors during the early spring and plant outdoors after the last spring frost. Target a well-drained area in your yard with moderate to full shade for planting. Use a tiller or hoe to loosen dirt to a depth of one foot to 15 inches. Dig hole twice the diameter of the astilbe container and place compost in hole to a depth of two to four inches. Be sure to provide one to three feet of space between your astilbe holes.
  
  

Planting Your Astilbe

• Remove your astilbe from its container and place in the hole you have dug. Place the root ball even with the surface of the soil. Take displaced dirt and place around the root ball. Gently tamp down the dirt around the stem of the astilbe. Provide one inch of water per week either through hand-watering or rain.
  
  

Caring for Your Astilbe

• Apply compost one inch deep around your astilbe plant. Add a two-inch layer of mulch on top of the compost to keep the plant's roots damp and to discourage weed growth. Separate astilbe after three to four years because it multiplies in size rapidly. Plant removed clumps elsewhere in your garden.
  
  

Learning More About Astilbe

• Native to Asia and North America, astilbe grows most successfully in parts of the country with cool, wet summers. The plant can be found in growing zones 4 through 8, which spans a broad swathe of the U.S. from Montana and Minnesota south to northern Florida and northern Texas. Its blooms typically emerge in June and July, providing beautiful accents to shade gardens for a six-week period. While astilbe is generally resistant to diseases and pests, it has been known to be afflicted with certain disorders, including powdery mildew. That ailment is marked by a white, fuzzy layer on its upper leaves; eventually leaves will wilt, turn brown and fall to the ground. The best strategy in dealing with this is reducing humidity and trimming afflicted areas of the plant. Also be on watch for Fusarium wilt, which causes young plants to wilt and die. Attack that problem by improving drainage and aeration.