Disease & Pest Control for Vegetable Gardens

Environmental Control

• Environmental control is a major element of an integrated pest management program for disease and pests in vegetable gardens. Begin by selecting vegetable varieties that have inherent resistance to specific pests and disease, and buy plants that have been certified disease free. Keep garden areas tidy and free of debris, weeds, which often can host insect pests, and diseased or dead plant matter. Rotate the location of where you plant vegetable crops from year to year, and consider planting companion crops to draw insects from vegetable gardens. Common examples include marigolds, basil and garlic. Regularly check vegetable plants for signs of insect pests; you can remove many insects by handpicking.

Biological Methods

• Biological methods can also effectively control vegetable garden pests, and the first step is to learn to differentiate insect pests from their beneficial counterparts. Beneficial insects will prey on, eat and destroy the pesky bugs eating your vegetables. There are two ways to increase the number of beneficial insects in the garden. The first is to not use pesticide products because these kill both the pests and the beneficials. The second is to purchase select beneficial insects and release them into your vegetable garden. Examples of beneficial insects include damsel bugs, ladybugs and lacewings. You can also use biological controls to manage fungal disease. Look for fungicides containing beneficial species such as trichoderma, bacillus and streptomyces.

Organic Controls

• A third option to manage disease and other pests in the vegetable garden is to use organic controls. Organic pesticides differ from synthetically manufactured chemical ones because their ingredients derive from naturally occurring materials. For example, botanical sources, such as neem and pyrethrum, are commonly used in organic insecticides approved for use in vegetable gardens. In addition, you can use insecticidal soaps and horticultural vegetable and mineral oils to curb problems with aphids, mites and leafhoppers. If you are concerned about plant disease, use organic products to manage this problem; common examples include sulfur dusts, copper compounds, potassium bicarbonate and hydrogen dioxide.

Chemical Options

• Chemical control options for vegetable garden insects and disease are recommended as a last resort of pest management. As noted, synthetically derived garden pesticides are chemically manufactured and deemed safe by the U.S. Environmental Protection Agency. To manage insect infestations in the vegetable garden, look for products containing carbaryl, diazinon or malathion. Common plant diseases such as blight, wilt and molds may be prevented using chemical options with ingredients such as chlorothalonil, mancozeb and PCNB.