Flea Beetle

• Tiny, round shothole damage — leaves look like they were peppered with a pin
• Small, shiny black or bronze beetles that jump when disturbed
• Seedlings may be seriously stunted or killed in heavy infestations
• Damage concentrated on youngest leaves and growing tips
• Worse in the first four to six weeks after transplant or germination

Adults overwinter in soil and leaf litter, emerging in early spring when soil temperatures reach around 50°F. They feed on seedlings and young transplants through late spring and early summer. Eggs are laid in the soil at the base of plants; larvae feed on roots, then pupate. One to two generations occur per year. Pressure typically diminishes as plants mature and harden off.

1. 01Cover seedlings and transplants with floating row cover immediately — this is the most reliable protection during the vulnerable window
2. 02Transplant established, stocky seedlings rather than direct-seeding when flea beetle pressure is high
3. 03Apply kaolin clay (Surround) to leaf surfaces — it physically deters feeding
4. 04Sticky yellow traps at plant level can monitor pressure but won't control large populations alone
5. 05Diatomaceous earth sprinkled on foliage may help suppress feeding
6. 06Spinosad can reduce adult populations in severe cases; apply in the evening to reduce bee exposure

If seedlings keep getting hammered at the same time each spring and row cover isn't feasible for your situation, an extension office can advise on the specific species in your area and whether later planting dates would reliably miss the emergence window.

• Flea Beetles in Vegetable Gardens— University of Minnesota Extension
• Flea Beetle Management— Penn State Extension