Question
I just noticed that I was getting weird coloring on some of my swiss chard and spinach leaves. It looks like something is burrowing in the leaves. I did a little research and narrowed it down to leafminers. What can I do to get rid of these pests?
Maria
San Francisco
Answer
Those are indeed leaf miners. The adults are small black flies that emerge from small brown pupae in either your soil or the neighbors. They are active from April to September. The adult flies lay white eggs on the undersides of chard, spinach, and beet leaves. The young burrow between the leaf surfaces, and once there, are impervious to sprays.
The goal is to keep them from maturing. Check leaves often for signs of eggs and destroy them. Remove portions of leaves that are infected by leaf miner and dispose of them (don't compost them). You can protect plants from the flies by covering them with floating row covers (We sell Harvest Guard). You can also spray your plants once a week with the organic Spinosad. It works by killing new egg hatches.
Share this post
