Earwigs are a common garden nuisance known for the damage they inflict on plants, soft fruits, and emerging seedlings. These nocturnal insects are drawn to moist, sheltered environments. They are especially problematic in damp conditions, leaving their daytime hiding spots to forage on vegetation at night. Successfully managing an earwig population requires a multi-step approach, combining observation with targeted physical and material controls. This guide provides actionable steps to confirm their presence and remove them from your garden.
Confirming the Culprit and Damage
Identifying earwigs is the first step in control, as their damage can often be confused with that of slugs or snails. Adult earwigs are reddish-brown insects, typically about three-quarters of an inch long, easily recognized by the prominent, forceps-like pincers extending from the rear of their abdomen. Since they are nocturnal, you will rarely see them feeding on your plants during the day.
The most telling sign of an infestation is the damage left behind: irregular, ragged holes chewed into leaves and flower petals, often without the slime trails associated with mollusks. They favor soft fruits like strawberries and corn silks, leaving shallow gouges. During daylight hours, earwigs seek dark, damp places, so you can often find them hiding under mulch, potted plants, stones, or garden debris near the damaged area.
Trapping and Manual Removal Techniques
Physical trapping is an effective, non-chemical method for reducing localized earwig populations. A simple approach involves creating oil pit traps using small, shallow containers like tuna cans. Fill the container with vegetable oil and a dash of soy sauce or bacon grease, which acts as an attractant. Bury the trap so the rim is level with the soil surface, allowing the earwigs to fall in but be unable to escape the slick oil.
Alternatively, use shelter traps, which capitalize on the earwigs’ need for a dark, moist place to hide during the day. Roll up a damp newspaper, corrugated cardboard, or a hollow piece of bamboo, and place it near the affected plants in the evening.
In the early morning, collect the oil traps and dispose of the trapped insects. If using shelter traps, unroll them and empty the collected earwigs into a bucket of soapy water. For quick reduction of pests directly on the plant, manually remove them by shaking the plant over a container in the morning, or use a flashlight to hand-pick them off the foliage at night.
Applying Targeted Control Substances
Once the population is reduced using traps, applying targeted substances creates a protective barrier against new earwigs. A popular organic option is food-grade Diatomaceous Earth (DE), a fine powder made from fossilized diatoms. DE works mechanically: its microscopic, sharp edges cut the earwig’s protective outer layer, causing the insect to dehydrate and die.
Apply a thin, even layer of the dry powder around the base of affected plants or along the garden bed perimeter. Because DE loses effectiveness when wet, reapplication is necessary after rain or heavy watering. For light infestations directly on foliage, insecticidal soap sprays or neem oil solutions can coat the insects and disrupt their membranes.
For a more persistent treatment, consider granular baits containing active ingredients such as Spinosad, a naturally derived substance. These baits are applied to the soil surface or garden perimeter, not directly onto the plants, and work when earwigs consume them while foraging. Always follow the product label directions precisely, especially when treating edible crops.
Long-Term Prevention Strategies
Preventing future infestations centers on eliminating the damp, dark environments that earwigs seek for shelter and breeding. Earwigs are strongly attracted to moisture, so reducing excess water in the garden is a primary preventative measure. Ensure good drainage and fix any leaky outdoor faucets or hoses near garden beds.
Clear away potential hiding spots, such as piles of leaves, decaying plant debris, boards, or excess mulch. Mulch should be kept to a minimal depth, especially against plant stems and foundations, as it provides a cool, moist habitat. Sealing cracks and crevices in raised beds, retaining walls, or the home’s foundation can also prevent earwigs from establishing colonies.