It may be necessary to protect plants from cutworms by fitting paper or metal collars around stems at transplant time. Aphids can be washed from plants with a garden hose or repelled by using a dust of Sevin or Rotenone. Slugs and snails are attracted to peppers. They have been known to strip a plant down to its main stem overnight during periods of wet weather. They can be controlled by putting down slug bait in shallow dishes near the plants.
Flea beetles chew tiny holes in the leaves. If infestations occur early, pepper plants are weakened and die. Sevin and rotenone repel flea beetles. The Colorado potato beetle is another pest that is controlled in the same manner.
Tomato hornworms are occasionally attracted to pepper plants. They are easily controlled by hand picking, although the organic bacterial controls Dipel and Thuricide are also effective. Some years stem borers may enter plant stems and burrow up the middle, causing the pepper plant to suddenly wilt and die. Sevin and rotenone offer some protection.
Watch for accumulation of aphids on the underside of the leaves, especially near growing branch tips. When a large aphid population is present, sticky "honeydew" appears on the lower leaves and fruit. If this situation occurs, apply a suggested insecticide. Bacterial diseases may be transported on purchased transplants, so look over potential purchases carefully for any leaf spotting or stem cankers.
Tobacco mosaic disease can take a heavy toll on plants--not necessarily killing them, but weakening them sufficiently to reduce yields. It is best controlled by planting hybrid pepper varieties specifically resistant to the disease.
People who use tobacco should wash their hands with soap and water before handling pepper plants to prevent spread of tobacco mosaic disease. Grow resistant varieties if possible.
Like tomatoes--peppers are susceptible to a condition called blossom-end rot. This can occur when the pepper plant comes under stress, particularly from lack of moisture. It can also be caused by leaving transplants indoors in small pots for too long, resulting in flower formation before plant has developed sufficient leaf growth.