Earwigs are nocturnal pests that may cause problems in a garden by chewing on plant foliage. Young bedding plants and other small plants may be killed by earwigs if the pests are not eliminated before extensive damage is done. Because earwigs only come out at night and hide during the day, you won’t notice bugs on your plants, but holes in leaves are a good sign you may have an earwig problem. Practicing good garden sanitation and using insecticides with residual effects are helpful for controlling earwig infestations.
Rake up debris from around the plants and seal it in garbage bags for disposal. Earwigs may use yard waste as hiding places. The tidier your garden area, the easier it is to control these pests. If the plants require mulch, you can leave it but must apply an insecticide to the mulch to kill earwigs that may be hiding.
Place cans full of tuna oil or other kinds of fish oil in areas around the plants. According to the University of California, earwigs are attracted to fish oil. They will fall into the can and become trapped in the oil. Dump the cans out when they become full of dead pests, then replenish the fish oil.
Apply insecticide to mulch, if applicable. Sprays, granules or dusts may be used. Follow label directions exactly to prevent harm to plants.
Treat plants with dust or spray insecticides that have residual effects. According to the University of Illinois Extension, insecticides containing permethrin, cyfluthrin or carbaryl are among the insecticides effective for earwigs. Treat the plants just before nightfall, when the pests start to emerge, for fastest results.