Aphids may be tiny, but if the little pests are ignored, they will multiply rapidly and will quickly suck the life out of a healthy vegetable plant. Aphids can usually be found in clusters on young leaves and shoots, and are especially partial to peas, cucumbers, beans, melon, potatoes, squash, cabbage and tomatoes. Although it requires vigilance, you can prevent your vegetable harvest from being destroyed by the hungry pests.
Check garden plants for aphids at least twice every week. Aphids are more difficult to control in large numbers because the damaged leaves provide shelter for the aphids.
Blast the aphids with a forceful stream of water from your garden hose. Often this treatment will be enough to knock the pests off the leaves. Repeat as often as necessary.
Introduce predators such as ladybugs or lacewings to your garden. Predators that occur naturally in your garden are best, but predatory insects can also be purchased at garden supply centers.
Prune the plant if the aphids are localized to a few areas. Prune the infested leaves and shoots with garden shears. Fill a bucket with soapy water, and drop the infested leaves and shoots in the water before disposing of them.
Make a homemade aphid spray. Combine two cups of vegetable oil and 4 tsps. of dish soap with three cups of water. Spray the infected vegetables in the cool part of the day, as sunlight can magnify the mixture and scorch the plants.
Resort to insecticides only when nothing else works. If possible, use selective soap and oil-based insecticides, as chemical insecticides will also kill the aphids' natural predators. Treat only the infested plants. Read the label carefully and follow the instructions.