Answer: You may have cut your plants back a little too far and that's why it too them so long to recover. You can cut back grassy growth to 6?12" above soil to renew in late winter and again in mid-summer, if desired. Or, if you don't want to cut the entire plant all the way back each year, you can remove the dead foliage (usually found around the perimeter of the clump) throughout the growing season. This is what I do - but then I love to garden. If you don't have time, you may opt to cut the entire clump back each winter.
Best wishes with your garden!
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