What is clematis wilt?
Clematis wilt is a disease of clematis caused by the fungus Phoma clematidina (formerly Ascochyta clematidina). Many of the large-flowered hybrid cultivars are very susceptible, but the smaller flowered species appear to be much more resistant. Wilting has long been recognised as a serious problem in clematis. And although it is known that the fungus Phoma clematidina causes clematis wilt, there are cases of wilting when the fungus is not present. Research has clarified two important points: • Wilting in large-flowered hybrid cultivars may be caused by the Phoma clematidina. • Wilting in resistant hybrids and species clematis is very unlikely to be P. clematidina, and is probably caused by environmental problems. So, although all wilting in clematis is often blamed on fungal infection, it is most likely to be caused by environmental problems, (unless it is wilting of the more susceptible large-flowered hybrids). Clematis is a plant which, in the natural environment, prefers a deep and
