Managing Cane Borers in Hydrangeas: Prune Out the Damage

Hydrangea cane borers are frustrating because insecticides rarely reach the larvae tunneling inside the stems. The most reliable control is mechanical: strategic pruning. Examine each cane and cut it back progressively lower until you reach clean, undamaged wood—the borer is always above that point.

Collect and discard every clipping in the trash (not the compost pile) to remove the larvae from your garden. Repeat this inspection annually; it may take a couple of seasons, but consistently removing infested wood drives down the local borer population and restores plant vigor.