In the garden: Stocks, wallflowers and other ornamental brassicas
On Crops: Most brassica plants (vegetable and ornamentals)
Wherever host crops are grown
Tiny dark brown to black beetles, 2-3mm long, which can often be seen on leaves if you approach quietly. When disturbed, flea beetles jump away with the help of their powerful rear legs.
Flea beetles chew tiny round holes in the top sides of leaves, with damage to leafy greens being most severe in spring. New leaves are usually damaged first, giving them a lacy appearance.
Always rotate crops, and use row covers (garden fleece) to protect susceptible crops. Winter-grown brassicas are less affected as flea beetles are much less numerous. Because mustard is so attractive to flea beetles in spring, you can try planting it along the edge of your garden as a trap crop. Flea beetles moving into the garden will stop to colonize the mustard rather than moving into the garden.
Make white sticky traps to capture flea beetles as they jump.
Delay planting of susceptible crops. Grow plenty of flowers to attract beneficial insects, which prey on flea beetles. Use row covers as your primary defence against this pest.