Plants they attack
Flea beetles attack most vegetables, particularly cabbage-family plants, potatoes, and spinach. They also feed on flowers and weeds.
Related: 14 Natural Ways To Control Garden Pests
Why they're a problem
You can recognize flea beetle damage by the small, round holes the adults chew through leaves. These beetles are most damaging in early spring, when heavy infestations can actually kill seedlings. Larger plants usually survive and outgrow the damage, unless they were infected with a plant virus spread by the beetles. Larvae feed on plant roots.
Related: How To Time Your Planting To Avoid Garden Pests
Organic damage control
Plant susceptible plants as late as possible to avoid the most damaging generation.
Cover seedlings and potato shoots with floating row covers until adult beetles die off.
Lightly cultivate the soil around plants before and after planting to destroy any flea beetle eggs and larvae in the soil.
Flea beetles like to hide in cool, weedy areas. Prevent them from hopping onto your susceptible crops by surrounding the crops with a 3-foot-wide strip of frequently weeded bare ground.
Confuse the beetles by mixing up your plantings. Surround their favorite food plants with flowers and herbs like Queen Anne's lace, dill, and parsley, which attract beneficial insects.