Pull back the mulch on your perennials before new growth begins to protect tender shoots during the process of removal. You don't have to entirely remove most types of mulch. They can remain in place around the perennials to hold in moisture over the summer and keep down weeds. If the mulch is no more than 2-4 inches thick, it won't hurt to leave it in place. Most perennials will push up through it anyway. Plants sensitive to late-winter moisture may benefit from mulch removal, however. Chrysanthemums are a good example. If the soil remains too wet, their root systems may rot.