Dying individual or scattered stems in a mass planting or perennial clump can wilt or be killed for a variety of reasons. Stem-boring insect larvae, breakage due to wildlife, and certain infections (Southern Blight being one of several) can all result in stem collapse and leaf browning. Since a fungicide will not be effective for situations where a fungal or bacterial disease caused wilting and dieback, since such products cannot cure existing disease, all that can be done is to prune out the stems in decline, since once wilted, they rarely recover (if insufficient water is the culprit, usually more of the plant will be equally affected).

Miri