Answer: Most fall chores in the perennial garden simply have to wait until mid to late fall, especially cutting back the tops of plants. Cutting back plants too early may result in a sudden flush of soft growth at a time of year that is risky. The goal is to allow your perennials to become dormant according to their own natural schedule, responding to the cooler weather and shortening days. There will be plenty of mild days to cut things back selectively in late November and early December. Quite honestly, I wait until spring to cut away dead foliage. The garden doesn't look as neat all winter, but the dead foliage will lay on the ground and help protect the crown of the plant.
Best wishes with your garden!
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