Flea Beetles

Adult flea beetles are small, shiny, and often black, bronze, or striped, with noticeably enlarged hind femurs used for jumping. Feeding produces numerous small, rounded holes across the leaf surface, giving foliage a characteristic shot-hole appearance, most damaging on cotyledons and young true leaves.

Adults typically overwinter in soil, leaf litter, or field margins and become active as temperatures warm in spring, when they move into emerging crops. Eggs are laid in soil near host plants, and larvae of many species feed on roots before pupating; several generations can occur per season in warm climates.

Adult feeding on cotyledons and young leaves can kill seedlings outright or slow establishment, while damaged leaf tissue also increases susceptibility to disease entry and moisture loss. Root feeding by larvae of some species adds further stress, particularly in root and tuberous vegetables.

Host crops include cabbage, broccoli, radish, and eggplant, along with many other brassica and solanaceous vegetables.

Inspecting seedlings soon after emergence or transplanting, particularly on warm, sunny days when adults are most active, helps detect early shot-hole damage before stands are seriously affected. Yellow sticky traps can supplement visual counts in some settings.

Because young seedlings are most vulnerable, flea beetle management emphasises protecting the crop during establishment.

• Use row covers or similar physical barriers during the vulnerable seedling stage
• Time planting to avoid peak adult emergence where local patterns are known
• Conserve parasitic wasps and flies and predatory natural enemies
• Manage crop residue and weedy hosts that can support overwintering adults