Troubleshooting
Clematis 'Piilu' problems — and how to fix them
Clematis 'Piilu' (Clematis 'Piilu') 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
Sudden wilting and blackening of stems caused by the fungus Calophoma clematidina; cut all affected stems to ground level and dispose — do not compost; new shoots usually regrow from below soil.
Powdery mildew
White powdery coating on leaves in dry, warm conditions with poor airflow; improve circulation and water at the base, not overhead; remove and bin infected leaves.
Failure to re-bloom
'Piilu' is a Group 2 (light prune) clematis; over-pruning in late winter removes the old wood carrying early double flower buds — prune only lightly, removing dead or weak stems.
Slugs and snails
Emerging spring shoots are highly attractive to slugs; use copper tape on container rims or biological nematode control (Phasmarhabditis) around the crown.
Aphids on new growth
Soft aphid colonies cluster on spring shoot tips; spray with insecticidal soap, taking care to protect open flowers.
Prevent clematis 'piilu' problems before they start
Most clematis 'piilu' issues are care-mismatch, not bad luck. Dial in the basics:
Clematis 'Piilu' problems — FAQ
Why is my clematis 'piilu' clematis wilt?
Sudden wilting and blackening of stems caused by the fungus Calophoma clematidina; cut all affected stems to ground level and dispose — do not compost; new shoots usually regrow from below soil.
Why is my clematis 'piilu' powdery mildew?
White powdery coating on leaves in dry, warm conditions with poor airflow; improve circulation and water at the base, not overhead; remove and bin infected leaves.
Why is my clematis 'piilu' failure to re-bloom?
'Piilu' is a Group 2 (light prune) clematis; over-pruning in late winter removes the old wood carrying early double flower buds — prune only lightly, removing dead or weak stems.
Why is my clematis 'piilu' slugs and snails?
Emerging spring shoots are highly attractive to slugs; use copper tape on container rims or biological nematode control (Phasmarhabditis) around the crown.
Why is my clematis 'piilu' aphids on new growth?
Soft aphid colonies cluster on spring shoot tips; spray with insecticidal soap, taking care to protect open flowers.