Answer: Most perennials need some clean up in the fall after frost has killed the stems and foliage. Trim off the dead material. If there are evergreen rosettes or lower foliage that stays green, leave that in place. Then mulch around (not over top of) the plants to a depth of about three inches using an organic mulch. As long as your plants are considered winter hardy in your zone, that is all you should need to do.
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