06/08/2026
Hydrangea leaftier is a very common pest of smooth hydrangeas such as Annabelle Hydrangea and Incrediball Hydrangea. It’s the larval stage of a small moth (Olethreutes ferriferana) that is found throughout eastern North America, including southern Ontario.
What does it look like?
The caterpillar ties young leaves together with silk, creating a little pouch or envelope. Inside that shelter, it feeds on developing leaves and often the flower bud.
Typical signs:
* Leaves at the tips of branches are folded, cupped, or stuck together
* Leaves appear puckered or distorted
* A small green caterpillar with a dark head may be found inside
* Flower buds may be damaged or fail to develop normally
Will it kill the plant?
No. It’s mostly a cosmetic problem and rarely threatens the health of an established hydrangea. However, it can reduce flowering because the caterpillars often feed on developing flower buds.
What should you do?
The easiest and most effective control is manual removal:
1. Inspect plants in May and early June.
2. Pull apart the tied leaves.
3. Crush or dispose of the caterpillar inside.
Because the caterpillar is protected inside the leaf pouch, insecticides are often less effective once the leaves are tied together. Hand removal is usually all that’s needed for home gardens.
