Tiny little holes in the leaves of plants are most likely to be the handy work of the flea beetle…
The small flea beetle has small stripes down its back and hops away like a flea when disturbed. Young brassicas and mustard leaves (listed below) are amongst its favourite foods and they will eat several tiny holes like those pictured in a single leaf.
- Wild Rocket
- Pak Choi
To keep them at bay, cover plants with an insect proof mesh and add a mulch (this should stop the larvae from becoming adults). They will be less of a problem as the plant matures and later on in the summer. You can still eat the affected leaves of rocket, mizuna etc so it isn’t the end of the world, but it does make your crop look a little less impressive when it is covered in holes!