Not only has it eaten some of those deliciously sweet peas but it has also left its excrement in the pod. This article describes how to identify and treat the Pea Moth.
Identify Pea Moth
Inside the pea pod (not mange tout) you will first notice that a few of the peas have a brown substance around them. This is the excrement of the Pea Moth. Some of the peas will also be partially eaten.
The final clue, if you search well enough, will be a light brown / green tiny caterpillar. That is the pest which is eating your peas. Click the picture on the left to enlarge it and see the caterpillar.
Understanding the life cycle of the Pea Moth is key to tackling this pest. The larvae over-winter in the soil and around may time they begin to pupate, that is change from larvae to flying moths. So the first defence against this pest is crop rotation. Don't plant peas in soil which has grown peas over the last two years. Click here for more information on crop rotation.
The moths emerge any time between June and August, the key time is late June to mid-July. The pea Moths then lay eggs on the foliage of the pea plants. When the eggs hatch they move to the developing pea pods and drill a tiny hole in the pod which gives them access to their favourite food, peas! They live off the peas and in August / September they drill their way out of the pods and onto the soil where they over-winter ready to turn into moths next year.
The second line of defence is to stop the pea Moths from laying eggs on the foliage. To do this cover the pea plants with light horticultural fleece from early June until the peas are picked.
There are chemicals which can be sprayed on the pea plants which will kill the eggs laid by the moths, ask at your garden centre for more information or simply read the labels on the chemical container. But in our experience, even when the peas are attacked, only about one in fifteen pods are affected. And that's without using a covering of horticultural fleece. Crop rotation though, is essential.