Pepper plants offer many things to the home gardener in the way of variety, ease of growth, low maintenance and amount of harvest. Unfortunately, pepper plants also offer a good food source to a range of invasive insects. These insects cause a host of problems and, depending on the type of insect, spread quickly enough to destroy multiple plants. Understanding what to look for will help a gardener know what insects she may be dealing with and how best to control the problems.
Various types of insects affect pepper plants at various stages of development. Aphids, mites, various worms, beetles and borers are among the insects attacking pepper plants. Insects feed on various parts of the pepper plant. According to the North Carolina State University website, aphids, two-potted spider mites feed on juices from the plant; armyworms, maggots and beetles feed on the fruit.
Symptoms of insect problems on pepper plants can occur at any time. The Extension Service of North Carolina State University reports that yellowing leaves are a sign of spider mites; while holes or defoliation are signs of flea beetles, blister beeltes, tobacco hornworms or armyworms. Damage to fruit can result from pepper maggots, European leaf borer, pepper weevils, leaf-footed bugs, tarnished plant bugs and cabbage loopers. Honeydew is a sign of aphids.
Effects range from mild to severe depending on the insect and the amount of infestation. Aphids leave a black sooty mold on leaves; the leaves can be removed and the plant saved. Flea beetles and blister beetles can cause small holes or damage to leaf margins, according to the Extension Service at North Carolina State University. Pepper maggots can cause cherry peppers to prematurely turn red and cause other peppers to become dimpled and deformed. Pepper weevils can cause deformed fruit or cause the fruit to drop from the plant. European corn borers are more severe; information from the University of Kentucky states that infested peppers will abort, decay or show signs of rotting because water entered into where the borers fed.
The speed of infestation and damage is what causes severe losses. Aphid colonies can grow rapidly, according to the University of Kentucky. The larvae of the European corn borer will move to fresh pods and fruit once rot begins to set in; this allows one larvae to destroy several peppers. The University of Kentucky also states that the beet armyworm can move quickly from plant to plant, destroying leaves while young and fruit when older; small transplants are the armyworm's food of choice.
Control of insects on pepper plants varies with the insect. In most cases, early detection is the recommended first control method. Systematic application of insecticides within one to three weeks can control the population of many insects including aphids, spider mites, flea beetles and pepper weevils. Pepper maggots and the European corn borer are best controlled by daily or weekly sprays and traps.