Coleoptera: Chrysomelidae
Description
Adult flea beetles are small, elliptical, or oval-shaped and only 1/16 of an inch in length. They have large and powerful hind legs to jump away like fleas. To identify flea beetles, it is easier to look for signs of their damage on plants such as “shot holes” leaves than for the beetles themselves.
Life Cycle
Flea beetles overwinter as adults in the soil or beneath plant debris. They become active in early spring when temperatures reach 50 °F and begin feeding on weeds or early planted crops. In early summer, adults lay eggs in the soil at the base of plant stems. Eggs hatch in 11 to 14 days and grub-like larvae with off-white bodies and the brown head appears in the soil. Larvae feed on roots until fully grow up. When larval development is complete, it pupates in small earthen cells. Development from egg to adult takes about seven weeks. Adult flea beetles are particularly active on warm, calm, and sunny days.
Damage
Larvae of flea beetle feed on the root hairs and taproots of seedlings. In a few cases, larvae have been observed burrowing into the plant near the juncture of the root and stem.
Adult flea beetles feed on foliage, producing “shot holes” in the leaves. In leafy crops like lettuce or spinach, the holes can reduce the quality of the leaves.
Generally, flea beetles don’t cause fatal damage to established plants. The real danger is that the beetles can spread bacterial diseases, such as wilt and blight, from infected plants to healthy plants.
Get rid of Flea Beetles
You can control the larvae of flea beetle in your garden using entomopathogenic nematodes formulated in the organic pest control products below:
- Flea & Chinch Ball/ Nematode Sprayer Combo
- Nema Globe Flea & Chinch Bug Buster
Advice for Flea Beetles
- Flea beetles can be kept away from crops by planting strongly scented plants such as catnip, sage, mint, or hyssop. Some plants such as nasturtium, radishes, and basil can be used as “trap crops” to take the beetles’ focus off of more valuable plants.
- Soapy water can kill the flea beetles on contact. Mix one teaspoon of liquid soap with one liter of water in a sprayer. Some types of soap can damage sensitive plants, so test the solution on a few leaves before spraying the entire plant.
