Depending on the variety, their height ranges from 6 inches to 5 feet. In spite of the astilbe’s need for abundant moisture (dry spells will induce dormancy), some drainage during the winter months is necessary. Astilbes are heavy feeders, so regular soil amendment and fertilizer is important. The plant is vigorous without being invasive, and if you wish to propagate it, you can easily do so by layering. Layering is started by taking a branch that’s still attached to the plant and gently bending the middle down to touch the earth, covering it with soil. Roots will sprout along the part of the stem that’s underground, and it will eventually become a separate plant. Not all goat’s beard plants bloom equally—plants that produce male flowers (with many stamens per blossom) are showier than female plants.
