Earwigs

While decaying organic matter forms the largest part of their diet, earwigs also feed on the tender shoots, leaves, and blossoms of flowering plants and vegetables. Earwigs, being also carnivorous, are predators of insect larvae, slug eggs, aphids, and other garden pests. They sometimes even eat each other.

During the day, earwigs like to hide in cool, dark, moist places: under stones, in garden rubbish, tubular legs of garden furniture, wooden fences, hollow aluminium doors, and other cracks and crevices. Earwigs begin searching for food at dusk. In search of food and shelter, they crawl over the ground, climb houses, fences and trees, and may begin to wander into homes in June or July. Although they are accidental invaders, it is annoying to find these insects among food and clothes and occasionally between bed covers.

How can I get rid of earwigs?

Physical control

The best time to begin control measures is early spring, during dry, warm weather, when the earwigs are young. In populated areas, control works best when carried out on a neighbourhood or community basis.

• Cultivate the soil to disturb earwigs that lived through the winter and expose newly laid eggs to the dry surface where they are less likely to survive.
• Create a clean, low-moisture perimeter around your house foundation by trimming back vegetation and removing mulch, organic debris and other objects that can be used for shelter by earwigs.
• Repair leaky taps and downspouts, and make sure to direct water drains away from your foundation.
• Keep your lawn and garden free of excess debris and decaying organic matter to make it less attractive for earwigs. Don't allow grass clippings, fallen leaves, weeds, and old wood to accumulate except where organic materials are stacked for proper composting.
• Start vegetable gardens as early as possible to give plants a head start before the young (nymphs) come out from their nests in June.
• Remove any damaged produce in your garden right away: earwigs like feeding on fruits or vegetables that have holes or bruises caused by other insects or disease.
• Inspect cut flowers or vegetables before bringing them in from your garden, and remove any earwigs hiding between leaves or inside blooms.

Remember that even if earwigs are present, they are not always to blame for plant damage. Try a night tour of the garden with a flashlight to see if other nocturnal insects or slugs are present.

Trapping

Take advantage of the earwigs' habit of hiding in small, dark places by setting up simple traps in areas where they commonly go for shelter. You can use:

• pieces of corrugated (pleated) cardboard that are rolled up, secured with a rubber band, and stood on end
• flower pots can be stuffed with moistened straw or newspaper and left upside-down on the ground, propped up with a small stone to leave space for earwigs to crawl under
• hollow bamboo canes or short sections of old garden hose can be placed on the ground

For best results, the traps described above must be checked regularly and the trapped earwigs dropped into a pail of soapy water.

Traps that attract and kill earwigs can also be placed near foundations and other strategic places in the yard:

• Earwigs are strongly attracted to fish oil and, to a lesser extent, vegetable and other oils. Shallow containers (like sardine cans), partly filled with oil and buried to the rim in the soil will attract and trap many earwigs.
• Use empty unrinsed frozen juice containers. Fill the tins two-thirds of the way with water. Add liquid soap and place in strategic locations.

Products

When the earwigs in your home are a persistent problem, treatment with an insecticide is an option to consider, although the earwigs will eventually die out on their own. Remember, a more effective and long-term solution is to find and treat the outdoor source of the infestation.

If physical control methods are not enough, many products registered in Canada to control earwigs can be bought at garden centres or hardware stores. Keep in mind the most important target areas for treatments:

• around building foundations and sidewalks
• along fences, hedges, and woodpiles
• under shrubs and other ground covers

Most garden insecticides are only effective when the insect comes into direct contact with them. Large infestations may develop tolerances to a particular chemical being used.

• Set out baited pesticide products in small piles of pellets as bait stations, covering each pile securely with a board, shingle, or weighted foil plate to protect children and pets from exposure. Covering the bait stations also makes them more attractive to earwigs. Place bait stations in target areas where earwigs are noticed.
• Use dust products only where children and pets cannot come into contact with treated surfaces. The best time to apply insecticides is during warm, dry weather when the earwigs are young, in June or early July. Applications should be done during the evening so that residues are fresh when the earwigs become active. Do not water areas you've treated for at least two nights after application. Treatment later in the summer is less effective.
• Diatomaceous earth, a fine powder also known as silicon dioxide, is made up of crushed microscopic marine fossils. It can be applied indoors or outdoors and remains active until it is washed away. As insects crawl over the powder, their outer "skin" is scratched, causing them to dehydrate and die. When attractants are added and the insects ingest the powder, their digestive system is affected as well. This product is non-toxic to humans and pets, but be careful not to inhale the dust when applying it.
• Pesticide sprays and powders can safely be applied (as directed on the label) to ornamental plants and vegetables under attack. Do not apply insecticides to any flowers, including fruit and vegetable blossoms, as they may be very poisonous to bees.
• Insecticidal soaps can also be effective when used where they will contact earwigs directly. You may need to repeat applications at regular intervals. Always check the label directions for how often to apply.
• To discourage earwigs from invading your home, certain pesticides can be painted or sprayed around exterior window frames, doors, and the foundation and nearby soil (not on vegetation). Be sure to check labels to see which products can be used like this. Indoor spot treatments with a residual spray can be done along baseboards, drainpipes, and under the edges of carpets and surrounding rugs.