Clematis wilt

Clematis wilt (Calophoma clematidina). This fungus affects Clematis species.

Also known as:
Pho ma clematidina
Ascochyta clematidina

recognize clematis wilt
Leaf and stems suddenly wither, photo: Marilou Vincent

Clematis wilt (Calophoma clematidina). This fungus affects Clematis species. Spots appear on the leaves, followed by wilting of the stems. The stem weakens at the top and dies. Newly infected stems turn black. Sometimes healthy shoots still grow from the soil during the infestation.
Calophoma clematidina survives on dead plant material in the soil. Splashing (rain) water can transfer fungal spores to leaves and stems, causing contamination.
Once infected, the infection spreads rapidly and causes sudden wilting and death of the shoots. The root system is often unaffected, so that young shoots from under the ground can still grow again. Calophoma clematidina does not kill the plant; these usually die from exhaustion.
Withering and dying of shoots and stems can also be caused by infestation of the roots by honey fungus (Armillaria mellea) and/or Phytophthora root rot.

Affected plants

Remedy

Cut off affected stems to the ground and hope the Clematis sprouts again from the ground. Destroy the affected leaves and stems to prevent reinfestation. Disinfect the tools.

Prevention

Plant the Clematis on a soil that is not too wet or too dry and not in full sun. Weakened plants are susceptible to fungal infections, such as Calophoma clematidina .