Grasshoppers feed on garden plants, including peppers. They consume entire portions of the plant, including leaves, fruit, flowers and stems. In many cases, they simply eat all the leaves off of a plant before moving on to the next one. Once stripped of foliage, the plant cannot continue to produce the energy it needs to grow and survive, let alone produce peppers. In small infestations, which are more common in home gardens, grasshoppers will eat only some of the leaves, allowing the plant to survive, but will often consume the young tender peppers, ruining the harvest.
Keeping weeds, wildflowers and wild vegetation cleared away from the garden can help keep grasshoppers away. If grasshoppers are a regular problem, however, this is not usually enough to prevent an infestation. Cover peppers with floating row covers, netting, cones or other physical barriers to deny grasshoppers access to the plants. Neem oil can also discourage grasshoppers from attacking pepper plants. Spray the oil on the plant before the grasshoppers begin to appear in the garden.
For small infestations, hand-picking can reduce grasshopper populations and damage. Remove the grasshoppers from the plant and kill them so that they cannot reproduce or return. Attracting birds to the garden by hanging feeders and birdhouses may also help control grasshopper populations since many birds feed on the pests. Chickens released into the garden can also stop a grasshopper infestation, although it is possible the chickens will damage young pepper plants.
Pesticides are the most common way to control grasshoppers once they invade a garden. They are more effective, however, if applied to surrounding weeds and grassy areas prior to an invasion of the garden. Young grasshoppers hide out in weeds and grass and are more susceptible to the effects of pesticides. Once grasshoppers are in the garden, appropriate pesticides for use on pepper plants should contain carbaryl, permethrin or Nosema locustae. All of these pesticides have been certified as safe to use on fruits and vegetables.