Earwigs are common in gardens across North America, instantly recognizable by the prominent pair of pincer-like appendages, or cerci, extending from their abdomen. The European earwig is the most frequently encountered species. These creatures occupy a complex ecological niche, often acting as both a helpful predator and a frustrating pest depending on the environment and population size. Ultimately, the earwig is an omnivore whose role depends entirely on what food is most available at any given time.
Earwigs as Beneficial Garden Predators
Earwigs are opportunistic omnivores that actively hunt and consume a variety of small, soft-bodied insects. This predatory behavior makes them valuable contributors to natural pest control within a garden ecosystem. They feed on numerous common agricultural pests, including aphids, mites, and scale insects, helping to regulate populations that might otherwise damage plants. They also consume the eggs and larval stages of pest insects, breaking their life cycles before they cause extensive damage. Furthermore, earwigs are scavengers that consume decaying plant material, contributing to the breakdown of organic matter and the recycling of nutrients back into the soil.
Plant Damage and Home Invasions
While their appetite for pests is welcome, earwigs can quickly shift their focus to desirable plants, especially when their numbers are high or other food sources are scarce. They are nocturnal feeders, so the signs of their presence are often apparent only by morning. Earwig feeding typically results in small, ragged holes chewed into leaves and flower petals, a damage pattern that can be confused with slugs but lacks the characteristic slime trail. Tender plant tissues are particularly vulnerable, including young seedlings, soft fruits like strawberries and apricots, and the silk of sweet corn. They commonly target ornamental flowers like dahlias, zinnias, and roses, chewing irregular holes in the blooms and foliage. This damage is usually cosmetic on established plants but can be devastating to new sprouts and commercially valuable produce.
Earwigs also become nuisance pests when they invade human dwellings, typically seeking moisture or shelter from extreme weather. They prefer dark, damp environments and congregate in areas like bathrooms, laundry rooms, and damp basements. They enter homes through cracks and gaps in the foundation, poorly sealed doorways, and unscreened vents. While they rarely establish permanent indoor colonies, their sudden appearance in large numbers can be alarming and is often a sign of high moisture levels outside the home.
Debunking Common Fears
The earwig’s name is derived from centuries-old folklore suggesting the insect crawls into the ears of sleeping people. This myth claims they burrow into the brain or lay eggs within the ear canal, but this is medically unfounded and inaccurate. Earwigs are primarily attracted to dark, moist crevices, such as leaf litter and mulch, environments structurally unlike the dry confines of the human ear. While any small insect could accidentally wander into an ear, such incidents are exceptionally rare and not a targeted behavior of the earwig. The insects’ prominent pincers look intimidating, but they are used for defense, courtship, and capturing prey, and are generally harmless to humans.
Balancing Presence: Encouraging and Deterring Earwigs
Effective earwig management requires a balanced approach: encouraging their beneficial predatory actions while deterring them from vulnerable plants and homes. To promote their presence as natural pest control, gardeners can provide sheltered, moist resting places. Simple, rolled-up newspapers or short sections of garden hose placed near aphid-infested plants act as desirable daytime hiding spots.
Conversely, if plant damage is problematic, simple trapping methods can reduce the local population without relying on broad-spectrum insecticides. Shallow cans containing a mixture of vegetable oil and a drop of fish oil or soy sauce, sunk into the ground at soil level, effectively attract and drown many earwigs. To protect specific plants, a sticky barrier applied to the base of fruit trees prevents the nocturnal climbers from reaching soft fruit.
To prevent home invasions, the primary strategy involves reducing moisture and hiding spots around the foundation of the house. This includes clearing debris, leaf litter, and excessive mulch away from the perimeter. Indoors, using dehumidifiers in damp areas like basements and sealing exterior cracks and gaps with caulk will eliminate the conditions that attract these moisture-seeking insects. By managing the conditions that favor them, it is possible to maintain a healthy earwig population that benefits the garden without becoming a household pest.