IDENTIFICATION — Orange, green, yellow, red, brown, black or covered with a waxy white or gray coating — there are all kinds of aphids out there. Most are 1/16 to 1/8 in. long, although some are bigger.
DAMAGE — Most aphid species are specific to one kind of plant, but they all pierce plant tissue, then suck out fluids. You’ll often find them in big clusters on new growth tips. A few aphids won’t hurt anything, but the population can grow rapidly. Large numbers of aphids cause curling, distorted leaves, yellowing foliage and stunted growth. They may also transmit diseases from plant to plant.
CONTROL — Keep an eye out for aphids. They reproduce so quickly that it takes no time at all before they’re all over your plants. Don’t overfertilize — high nitrogen causes lots of lush, tender new growth that attracts aphids. Prune out infested twigs and dispose of them, or hose aphids off plants with a strong jet of water.
Insecticidal soap controls aphids, but be sure to cover them completely with the spray. You can also use aphid predators, such as parasitic wasps and ladybugs, to feed on the pests. This control takes some time to work, so it isn’t the best way to get rid of aphids quickly.
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