Common Vegetable Garden Insects Pests

Pest Vegetables Identification Control
Tomato Hornworm Tomato, eggplant, pepper, potato Large green caterpillar with white chevrons on side. Leaves chewed starting at top of plant. Handpick, but leave any caterpillars that have white rice-like things stuck to their backs; these are parasitic wasps’ eggs. Rototilling soil after harvest destroys pupae.
Imported Cabbage Worm Cabbage, kale, broccoli, cauliflower, celery, parsley Pretty white butterflies in early summer, small green caterpillars with faint yellow marking. Holes in leaves Control weeds around the garden, especially mustard family. Remove cabbage plants in fall and destroy or bury to defeat over-wintering pupae. Use floating row covers; leave them on till harvest. Hand pick larvae.
Cucumber Beetle Cucumber, muskmelon, watermelon, pumpkin, squash Long beetle, either yellow with 3 black stripes, or yellow-green with 12 black spots. Holes in leaves, wilted plants (these bugs can spread bacterial wilt) Use floating row covers until plants flower. Hand pick larvae.
Mexican Bean Beetle Beans Roundish coppery brown beetle with black spots. Bright yellow, spiny oval larvae that feed on the underside of leaves. Bean leaves chewed Plant bush beans instead of pole beans so you can use floating row covers; remove row covers for harvest (bush beans don’t require pollinators to set fruit). Handpick adults and larvae.
Squash Bug Summer squash, winter squash, pumpkins Brown “stink bug” shaped adults, light gray tear-drop shaped nymphs. Yellow spots on leaves or fruit, wilting vines but stem looks sound. Handpick adults, nymphs and eggs (laid on the underside of the leaves). Use floating row covers till plants bloom. Place a shingle on ground near plants; insects will collect under it at night and can be picked in the morning.
Squash Vine Borer Summer squash, winter squash, pumpkins Large holes near the base of the stem with yellowish-green frass. Plants may be withered. Use floating row covers till plants flower. Put out yellow buckets of water in mid-June through July; the adult moths are attracted to yellow and may drown. Cut open stem and dig borer out; bury slit stem in soil to encourage re-rooting.

Hand-picking: Put some soapy water in a jar or small bucket. Drop insects into the water, or knock them off the plant directly into the water. The soap will make sure they break through the water surface tension and help them drown. Let the bucket sit for an hour or so, and then dump it out.

Floating row cover: Also known as “garden fabric”, a floating row cover is a temporary barrier that bugs can’t get through but sunlight and rain can. This polypropylene sheet is tucked into the ground on either side of the row and held above the crop foliage with wire or plastic hoops. If you are growing the plant for fruit (e.g. squash) rather than leaves (e.g. cabbage), the barrier needs to be removed when the plant blooms to allow access by pollinators.


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