Aphid Pest Control

Aphids are pesky little critters who usually top a gardener’s list of “most hated” insect pests. The tiny pearly green or milky white insects are almost impossible to avoid. They love just about all vegetables and ornamentals. Apple trees, roses, and beans are especially susceptible to aphid attack, and symptoms of aphid infestation include curled leaves, deformed fruit, and honeydew secretions on the plant. Fortunately, aphids can be controlled well with several cultural practices, and chemical controls are seldom necessary.

The first defense against aphids is to maintain your own presence in the garden. Check daily for signs of their moving in. Aphids are tiny with pear-shaped bodies and two antennae from their forehead. Often, they are accompanied by ants, which like to feed on the honeydew that aphids secrete. You may notice the ants before you notice the aphids. Look under the leaves especially.

Once aphids are noticed, act quickly. They don’t waste any time multiplying. If left unchecked, they can suck nutrients from plants and spread deadly plant viruses such as mosaic virus.

Natural Solutions

First, spray the plant with a stream of water to wash the aphids off. Then allow the plant to dry and begin a treatment. A very effective control for aphids is a simple soap spray. Mix 4 ounces (about 3 tablespoons) dishwashing liquid to one gallon of water. Spray the plant, being sure to get under the leaves as well as on the leaf surfaces. The soap spray fades away quickly, so you will need to repeat spraying often.

Soap sprays usually result in aphid death in about an hour. After an hour, you can wash the plant with pure water if desired. Washing with water is most desirable with melons, cucumbers and African violets, which can suffer leaf burn if the soap spray stays on too long.

Got too many hot peppers coming in? Hot pepper sprays are also an effective aphid control. Garlic also works. An easy anti-aphid cocktail combines 3-4 hot peppers, a few cloves of garlic, and 1 quart of water. Mix it all in the blender, then spray on plants.

Another good cultural practice for aphid control is interplanting your ornamentals with basil. Aphids are repelled by the smell of the basil. Also, plant angelica and morning glory to attract ladybugs, a natural predator of aphids. Ladybugs can be purchased in some garden supply stores or through organic gardening retailers. Start with about 100 ladybugs per 1000 square feet of garden space. Release them in the evening so they can have dew to drink.

-Mary Lusk

Mary Lusk is a freelance gardening/agriculture writer with a master's degree in soil science. She frequently writes about how gardeners can improve or work with the condition of their soil to get the most from their gardens.