Integrated pest management (IPM) is recommended by the Environmental Protection Agency (EPA) for organic pest control. IPM focuses on long-term prevention of disease and pest problems through a combination of techniques including the use of organic pesticides when necessary. Other pest management techniques include companion planting and use of beneficial insects. Organic pesticides for vegetables are derived from natural substances; they are not toxic to animals and people and they break down relatively quickly and harmlessly in the environment. There are many commercially produced organic pesticides for vegetables and several that can be made at home.
Prevention is the best cure but sometimes aphids, mealybugs and spider mites take over the vegetable garden. Garlic repels them and oil ensures that it sticks to plants. Soak a whole bulb of chopped garlic in two tablespoons of mineral oil for 24 hours. Dissolve two teaspoons of dish soap in a cup of water and add the garlic/oil mixture. This mixture can be saved in a glass jar and used in a one to 50 parts ratio when needed. Garlic oil spray repels aphids, snails, caterpillars and flies.
Simple soap spray kills caterpillars, aphids, thrip, scale, mites and whiteflies. It suffocates these insects and is most effective when sprayed directly on them. Use several tablespoons of dish soap to a quart of water and shake until it becomes frothy. Spray directly on plants and allow to dry overnight. Rinse plant leaves the next day and repeat this process for two to three weeks.
Milk is lethal to red spider mites and mildew. Zucchini, lettuce, cucumber and tomatoes are susceptible to mildew problems and milk spray is a simple remedy. It is made by mixing equal parts milk and water. Use the spray every few days until the disease is controlled.
Chamomile tea spray is the gentlest fungicide available to use for powdery mildew, rust, leaf spot and brown rot. The tea is brewed and left to sit for several hours before using. Repeat the spray process every few days until the fungal problem abates.
Eucalyptus and other essential oils are effective against scale, aphids, mites, slugs and whiteflies. Add one teaspoon oil to two cups water to make the spray. It is used at the base of plants and on seedlings. For best results repeat this process every three days.