Answer: The rule of thumb is to remove anything that is brown and leave anything that is still green and healthy looking at any time of year. Removing the faded foliage helps prevent carry over of any insect or disease problem from year to year and helps keep the rhizomes from rotting. Also clean away any fall leaves so they don't build up over top of the rhizomes where they could trap moisture over the winter. Trimming the leaves prematurely can reduce the plant's ability to store energy for a good blooming performance the following year.
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