Aphids are common insects that feed on many garden and landscape plants. In low or moderate numbers, aphids do not significantly damage plants and can often be washed away with water. When aphid populations increase, natural predators like ladybugs and lacewings will feed on them, reducing the need for pesticides. Non-chemical methods like pruning infested plant parts and using high-pressure water sprays can help control aphid numbers. If pesticides are needed, soaps and oils are safer options that work by smothering aphids.