Troubleshooting
Clematis problems — and how to fix them
Clematis (Clematis spp.) is generally forgiving once you match its basics, but a few issues come up again and again. Here is what each one looks like, why it happens, and the fix.
Clematis wilt
The fungus Calophoma clematidina invades the stems and blocks water-conducting tissue, causing sudden wilting, leaf spotting and blackening of stems near soil level, mainly in large-flowered hybrids.
Powdery mildew
A white fungal coating on leaves and shoots that is encouraged by water stress and poor air circulation around the plant.
Aphids
Sap-sucking insects cluster at shoot tips, stunting growth and coating foliage in sticky honeydew that can develop black sooty mould.
Slime flux
A frothy, foul-smelling ooze seeps from the stems when bacteria enter through frost or mechanical damage to the woody tissue.
Few or no flowers
Usually caused by too much shade on the top growth, incorrect pruning for the plant's pruning group, or excess nitrogen feed driving leafy growth.
Slugs, snails and earwigs
These pests chew young shoots and leaves, especially on new spring growth and container plants.
Prevent clematis problems before they start
Most clematis issues are care-mismatch, not bad luck. Dial in the basics:
Clematis problems — FAQ
Why is my clematis clematis wilt?
The fungus Calophoma clematidina invades the stems and blocks water-conducting tissue, causing sudden wilting, leaf spotting and blackening of stems near soil level, mainly in large-flowered hybrids.
Why is my clematis powdery mildew?
A white fungal coating on leaves and shoots that is encouraged by water stress and poor air circulation around the plant.
Why is my clematis aphids?
Sap-sucking insects cluster at shoot tips, stunting growth and coating foliage in sticky honeydew that can develop black sooty mould.
Why is my clematis slime flux?
A frothy, foul-smelling ooze seeps from the stems when bacteria enter through frost or mechanical damage to the woody tissue.
Why is my clematis few or no flowers?
Usually caused by too much shade on the top growth, incorrect pruning for the plant's pruning group, or excess nitrogen feed driving leafy growth.
Why is my clematis slugs, snails and earwigs?
These pests chew young shoots and leaves, especially on new spring growth and container plants.