hydrangea – leaf curl with worm inside

(Question)

I just today discovered all of my hydrangea bushes have this’ pod like’ problem – leaf curled tightly with worm inside – this is totally new to me – have never seen this problem till this year – what can I do?? – I’ve cut off all of these nasty pods – should I spray now??

 

(Answer)

Cutting off the `pods` was exactly the right thing to do. Your plants have been infested with one of two kinds of insects that create similar damage.

The hydrangea leaftier larva (caterpillar) binds two or as many as four leaves together with strands of silk into a cup form and then feeds and rests between them. Pulling the leaves apart will reveal a slender greenish caterpillar up to one-half inch long with a blackish head. After it stops feeding, the caterpillar will drop to the ground to pupate over the summer and emerge as an adult moth the next spring.

Leafier damage (photo University of Ilinois)

 

 

 

 

 

 

 

A different insect that causes similar damage is the leafroller. In this case, the caterpillar rolls or folds only one leaf, binds it with strands of silk, then feeds and rests within the rolled or folded leaf.  It sounds as though this may have been your culprit.

In both cases, the damage is unsightly but will not destroy the shrub. Because it occurs early in the spring, if you remove the infested leaves and smash the caterpillars, the plant will have time to grow and flourish over the summer. Make sure to clean up the ground below the shrubs very well.

References:  University of Illinios http://hyg.ipm.illinois.edu/article.php?id=359

and US Dept of Agriculture via link from http://slugginalong.blogspot.ca/2012/10/leaf-rollers.html