Earwigs are nocturnal insects often found in gardens and occasionally indoors. They are recognizable by the prominent pincer-like appendages, or cerci, on their abdomen. Classified as omnivores, they consume both plant and animal matter. Earwigs are not inherently harmful, but they become a nuisance when they congregate in large numbers or damage tender garden plants. Their presence is highly dependent on specific environmental conditions, primarily the availability of moisture, shelter, and food.
The Essential Draw: High Moisture and Humidity
The strongest attractant for earwigs is a consistently moist environment. They are highly vulnerable to desiccation (drying out) and must actively seek areas where the air is humid and where they can contact damp materials to prevent water loss during the day.
This need means any source of excess water around a home becomes an earwig magnet. Common outdoor sources include overly saturated garden beds, poorly draining soil near the foundation, leaky faucets, sweating pipes, and condensation from air conditioning units. Inside the home, earwigs gravitate toward high-humidity areas like basements, crawl spaces, laundry rooms, and bathrooms, often signaling an underlying moisture issue.
Preferred Hiding Spots and Structural Shelter
Earwigs are strongly attracted to tight, dark, and secluded spaces that offer refuge during daylight hours. This instinct, known as thigmotaxis, is the drive to seek physical contact with surfaces for protection. They emerge at night to forage but must find a secure hiding place before dawn.
Certain materials make highly desirable hiding spots, regardless of their moisture content, such as piles of newspapers, stacks of cardboard, and loose leaf litter. Outdoors, earwigs congregate under stones, patio pavers, and pieces of wood, while cracks in a building’s foundation offer easy access to interior spaces.
Primary Food Sources
Earwigs are generalist scavengers with a diverse, omnivorous diet. A major component of their diet is decaying organic matter, such as dead leaves, mulch, and compost, which is readily available in garden settings.
When populations are high, earwigs also feed on soft, living plant material, including flower petals, tender sprouts, and soft fruits like berries, often causing noticeable damage. They consume fungi and mold, which flourish in damp areas. Earwigs also act as minor predators, consuming small, soft-bodied insects like aphids, mites, and insect eggs, drawing them into areas where these prey species are abundant.
Modifying the Environment to Reduce Attraction
Reducing earwig presence involves systematically eliminating the attractive factors of moisture, shelter, and food. Addressing water sources is the foundational step, requiring the repair of leaky plumbing, ensuring gutters drain properly, and grading soil so water flows away from the foundation. Using a dehumidifier in damp interior spaces like basements or crawl spaces will lower ambient humidity, making the environment inhospitable.
Structural modifications focus on removing materials that provide daytime shelter. Mulch and dense ground cover should be pulled back several inches from the foundation to create a dry barrier. Piles of firewood, lumber, or yard debris should be stored off the ground and away from the house exterior. Removing accessible food sources means regularly cleaning up fallen fruit, pulling weeds, and promptly disposing of leaf litter and dead plant material from garden beds.