On Crops: Arugula, mustard, bok choy, cabbage family crops, potatoes, eggplant, tomatoes
Worldwide, wherever host crops are grown
Tiny dark brown to black beetles, 2-3mm (about 1/10in) long, can 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 most severe in spring. New leaves are usually damaged first, giving them a lacy appearance. The flea beetle species that attacks eggplant and tomato family crops cause similar damage during the warm summer months.
Always rotate crops, and use row covers (garden fleece) to protect susceptible crops. Grow most of your mustard and Asian greens in the fall, when 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. You can apply spinosad (a biological pesticide), but flea beetle populations may rebound in a few days, so the fight will not be over.
Delay planting of susceptible crops. Grow plenty of flowers to attract beneficial insects, which prey on flea beetles. Use row covers as your primary defense against this pest.