Answer: As with most perennials, the bloom period of astilbe is only a few short weeks. There is not too much you can do to prolong it. Once the flowers turn brown, remove the bloom stems by trimming them off at the base. Astilbes will grow best in morning sun and a rich, moisture retentive soil with plenty of organic matter added. Using an organic mulch will help to keep the soil moist and will also feed the soil over time as it breaks down. Enjoy your astilbes!
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