Plant Doctor Archive

Roses under attack

I HAVE a rose problem. I've spotted a little caterpillar getting inside the leaves and sticking them together with its cocoon. It's eating the leaves quite quickly and I can't find it in any of my rose books. Please help!

IT looks like the problem is leafroller caterpillar, of which there are several different types. The caterpillar is the larvae of a moth which can attack a wide variety of plants, ranging from fruiting and ornamental trees to perennials and shrubs.

They're not a common problem of roses but will feed on them if that's where the female moth chooses to lay its eggs. The newly hatched caterpillar then folds over a leaf to build a shelter where it settles down to feed, safe from the weather and predators such as birds. Fortunately, they're seldom present in sufficient numbers to do a lot of damage to roses, but if they are problem, a spray such as Shield (which contains a fungicide as well), Maldison or Carbaryl should control them. Make sure to follow the instructions on the label. Or you could check your plants regularly for the tell-tale signs of folded over leaves and simply squeeze them to kill its leaf-eating occupant.

Reproduced with permission from the former Weekend Gardener magazine. The views expressed here are not necessarily those of the RNZIH.