Troubleshooting
Hairy Hydrangea problems — and how to fix them
Hairy Hydrangea (Hydrangea involucrata) 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.
Leaf scorch
Brown leaf edges from too much direct afternoon sun or drought stress; move to a shadier spot and water consistently.
Powdery mildew
White powdery coating on leaves in humid, low-airflow conditions; improve air circulation and apply a dilute bicarbonate spray if needed.
Failure to flower
Often caused by pruning at the wrong time; this species blooms on old wood — prune only immediately after flowering.
Vine weevil
Notched leaf margins and wilting indicate root damage by vine weevil larvae; treat container plants with nematodes in late summer.
Chlorosis
Yellow leaves with green veins suggest iron deficiency from too-alkaline soil; lower pH with sulphur chips or ericaceous compost.
Prevent hairy hydrangea problems before they start
Most hairy hydrangea issues are care-mismatch, not bad luck. Dial in the basics:
Hairy Hydrangea problems — FAQ
Why is my hairy hydrangea leaf scorch?
Brown leaf edges from too much direct afternoon sun or drought stress; move to a shadier spot and water consistently.
Why is my hairy hydrangea powdery mildew?
White powdery coating on leaves in humid, low-airflow conditions; improve air circulation and apply a dilute bicarbonate spray if needed.
Why is my hairy hydrangea failure to flower?
Often caused by pruning at the wrong time; this species blooms on old wood — prune only immediately after flowering.
Why is my hairy hydrangea vine weevil?
Notched leaf margins and wilting indicate root damage by vine weevil larvae; treat container plants with nematodes in late summer.
Why is my hairy hydrangea chlorosis?
Yellow leaves with green veins suggest iron deficiency from too-alkaline soil; lower pH with sulphur chips or ericaceous compost.