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Aphids attack almost all vegetables. There are winged and non-winged aphid types. They suck the juice from the plants and some transmit viral diseases to plants. They attack potatoes as well. They can transmit potato leaf roll virus and potato virus Y, which affect growth and yield of potatoes. However, the aphids are minor pest in tomatoes, serious damage can occur when a large number of aphids attack tomatoes. The green peach aphid and other aphids tend to overwinter in the egg stage mainly on stone fruits such as plums and peaches while potato aphids overwinter on roses. The aphids attack pepper fields mainly in midsummer. The cabbage aphid is a problem in most brassica especially on Brussels sprouts. In pumpkins, squash, and other cucurbits they suck juices from the leaves and fruits and transmit virus mosaic pathogens. The pathogen causes a serious malformation on leaves of pumpkins and summer squash leading to poor yield and reduction in fruit quality.

For a heavy aphid infestation in a commercial field, use insecticides recommended in your state. Homeowners can spray with water to remove aphids from the leaves in a small garden. Ladybird beetles and other natural predators feed on aphids so do not spray with insecticides that can kill ladybird beetles. Also use fine netting row covers.