Insect Infestation Cures for Vegetable Plants

Realizing that bugs are beating you to your vegetables can be a frustrating experience. Inspect the garden frequently for pests. If the insect population is small, handpicking pests may be sufficient. Other measures include lures, baits and traps, but in the event of a larger infestation, the use of an insecticide may be necessary. Insecticides can be botanical (plant extract), microbial (bacterial based) or manufactured. Read each label to determine which insecticide is best suited for your garden.


Aphids affect a wide variety of vegetables by sucking plant sap and transmitting disease. These tiny insects vary in color and appear in large groups. Look for aphids during periods of rapid plant growth. If an infestation occurs, blast aphids with a powerful spray of water. For heavy aphid infestation use an insecticidal soap (potassium salts of fatty acids) or other insecticides such as malathion, neem oil or pyrethrins.

Squash Bug

Squash bugs feed on the cucurbit family, including cucumbers, melon, squash and pumpkin. They attack the leaves of the plant, sucking sap and causing wilt. These insects overwinter in garden debris, appearing in adult form as brown or gray bugs. They have flat backs and when turned over can be identified by their orange or brown striped abdomen. Look for the nymph (youth) or adult near the crown of the plant, underneath plant leaves or in garden debris. Handpick and destroy adult and nymph squash bugs. If there is evidence of heavy infestation, you can use an insecticidal soap (potassium salts of fatty acids). Other effective insecticides are kaolin clay, neem oil, permethrin, carbaryl or pyrethrins.

Tomato Hornworm

The tomato hornworm affects tomatoes, potatoes, eggplant and peppers. The hornworm is most destructive in caterpillar form. Look for large droppings below the affected plants. The caterpillars will be underneath leaves and can be handpicked and destroyed If you prefer an insecticide, use Bt (Bacillus thuringiensis), spinosad, carbaryl, kaolin clay, permethrin or pyrethrin.

Imported Cabbageworm

The cabbageworm feasts on the brassica family, which includes cauliflower, broccoli, cabbage and turnips. They overwinter in weeds and yard debris and return yearly, according to Cornell University New York State Agricultural Experiment Station. In adult form, it is a white butterfly that lays eggs on affected plants. Seeing the butterfly is an early predictor of an infestation to come. Look for caterpillars underneath leaves of plants while the leaves are still small and before the head has formed. If an infestation is found, handpick and destroy the caterpillars. You can also use an insecticide such as neem (azadirachtin), Bt (Bacillus thuringiensis), Spinosad, carbaryl, malathion and permethrin. An insecticidal soap may also be effective.

Corn Earworm

The corn earworm (also known as the tomato fruitworm) affects corn, tomatoes and beans. The adult form is a moth, which lays eggs in the silk. Once in caterpillar form, it starts at the tip of the ear of corn and works its way down the silk, eating the kernels. If an infestation occurs, apply Bt insecticide when tassels emerge. The University of California Agriculture and Natural Resources reports that to be effective, the insecticide must be used shortly after the eggs have hatched but prior to the caterpillar infesting the corn.

Keywords: insect control, insecticides, vegetable pests