As our season cools down and plants go dormant we start to see dead foliage on the perennial plants we have in our landscapes. Some people think this needs to be removed now. It is not necessary to clear-cut the perennial garden after the first freeze of the season. Leaving the leaves, stems, dried flowers, and seed heads of many perennials provides more interest through the winter months. Leaving the plant materials also provides an extra layer of protection for the crown and root system of the perennial. Plus, the dead stems and leaves collect fallen leaves, adding even more protection. Leaving the plant material in place and removing it in early spring instead of fall also helps provide food and protection to native pollinators, beneficial insects, and wildlife, such as birds.
While it is largely beneficial to leave the foliage in place through winter, removing plant material in the fall after it has naturally died back should be done for perennials with disease or insect pest issues during the summer. Additionally, those perennials that tend to be weedy or spread aggressively by seed benefit from late-season deadheading and clean-up to prevent them from being too weedy.
