When you see damage on hydrangea leaves, it’s most likely leafrollers.
Leafrollers are tiny green caterpillars that take hydrangea leaves and either (1) glue the leaf edges together with silk webbing or (2) take a single leaf and roll it up like a cigar.
The tiny caterpillars then hang out in these leaf nests, feeding and resting until it is time to pupate. Once they pupate, they will emerge as moths.
Chances are leafrollers won’t kill a hydrangea. However, the rolled and pinched leaves look unsightly and, if left unchecked, can reduce this season’s bloom production. And we all want our blooms!
How do you fix leafrollers?
Simple.
Gently open up the pinched or rolled leaves and run your finger over the surface of the hydrangea leaves, removing any webbing. If you see a tiny green caterpillar in there, simply just drop it in a pail of soapy water, or, for the braver gardener, squish the little green caterpillars with your fingers.
Leafrollers are typically active until early July, when they cease feeding on hydrangea foliage. Subsequently, they drop to the ground to pupate throughout the summer, preparing to emerge as adult moths the following spring—best of luck with your leafrollers.
Happy Gardening!