Hello Gardeners, I’m Amanda McNulty with Clemson Extension and Making It Grow. Often people call the office and tell us that lichens are killing their plants. Lichens however, live independently of the surface, or substrate, they’re growing on-- they don’t have any root-like structures to extract nutrients. When growing on woody plants, they’re simply using them as a way to be in the sunlight. Lichens can be just as healthy growing on tombstones, walls, or rocks. In older landscapes, where azaleas and camellias may have been neglected for decades and as a result have less vigorous growth with fewer leaves, lichens often take advantage of those more open spaces. We encourage people who worry about lichens to invigorate older plants by following the directions for rejuvenation pruning at Clemson factsheet 1053, pruning shrubs. Other landscape materials, such as boxwood, need a less drastic process and you must spend several years slowly doing renewal pruning on them.
Lichens
