Earwigs chew irregular holes in leaves, devour seedlings, and gouge into soft fruits, with damage peaking from late June through October. They feed mostly at night, which means you’ll often see the destruction before you ever spot the pest responsible. Knowing what earwig damage looks like, which plants are most at risk, and how to fight back can save a garden season.
What Earwig Damage Looks Like
The telltale sign on established plants is ragged, irregular holes in the leaves or edges that look like they’ve been nibbled away unevenly. Unlike the clean, round holes left by some beetles, earwig feeding creates rough, uneven edges with no consistent pattern. On older plants, including fruit trees, you’ll often see numerous holes scattered across a single leaf rather than one large missing section.
Seedlings get hit the hardest. A young plant attacked by earwigs may be missing entire leaves or have its stem chewed partway through, sometimes collapsing overnight. If you walk out to your garden and a row of new transplants looks like it was mowed down at soil level, earwigs are a likely culprit, especially if the damage appeared between dusk and dawn.
Flowers take a beating too. Dahlias, zinnias, and marigolds are favorites, and the damage shows up as tattered, hole-riddled petals that ruin the bloom’s appearance. On corn, earwigs feed on the silks and can actually prevent pollination, leading to ears with patchy, undeveloped kernels.
Damage on Fruits and Berries
On stone fruits like peaches and plums, earwig damage typically appears as shallow surface gouges, irregular in shape but with rounded edges. Occasionally an earwig will bore deeper and feed on the flesh near the pit. Apples are vulnerable too, particularly softer-fleshed and open-calyx varieties. Earwigs are often found feeding inside stem bowl splits on apples, which they enlarge over time. This can make it look like they caused the initial crack, when they actually moved into damage started by birds or caterpillars.
That secondary feeding habit is worth noting: earwigs are opportunists. Any wound on a fruit, whether from hail, a bird peck, or another insect, becomes an entry point. Once inside, they expand the damage and can accelerate rot. Strawberries, sitting close to damp soil where earwigs hide during the day, are particularly easy targets.
Plants Most at Risk
Earwigs aren’t picky, but they do have clear preferences. The most commonly targeted plants include:
- Vegetables: lettuce, celery, potatoes, seedling beans and beets, sweetcorn
- Fruits: strawberries, stone fruits (peaches, plums), soft-fleshed apples
- Flowers: dahlias, zinnias, marigolds, roses, hollyhocks, hostas
- Other: clover, butterfly bush, tender grass shoots and roots
Young, tender growth is always more vulnerable than mature foliage. A garden full of freshly transplanted seedlings in early summer, right when earwig populations are surging, is essentially a buffet.
How to Tell Earwig Damage From Slugs or Caterpillars
Earwigs, slugs, and caterpillars all chew holes in leaves, flowers, and fruits, and all three can destroy seedlings. The overlap makes identification tricky, but a few differences help narrow it down.
Slugs and snails leave shiny, slimy trails on leaves and soil. If you see that silvery residue near the damage, earwigs are off the hook. Caterpillar damage often appears as larger, cleaner-edged holes or leaves stripped down to their veins, and you can usually find frass (small dark droppings) on or below the plant.
Earwig damage is the hardest of the three to identify with certainty because earwigs leave no trail and no droppings you’d easily notice. The best confirmation method is a nighttime inspection with a flashlight. Earwigs hide in dark, moist crevices during the day and emerge after dark. If you check your damaged plants around 10 or 11 p.m. and find earwigs actively feeding, you have your answer.
When Damage Is Worst
Earwigs mate in fall, overwinter as pairs in underground nests, and the females lay eggs in early spring. Those eggs hatch in about a week, and the young nymphs emerge from the soil sometime between late May and early June. By late June or early July, they’ve matured into adults, and this is when garden damage starts escalating. Feeding continues through fall, making the window from late June to October the primary damage season.
July and August tend to be the peak months. This is also when earwigs are most likely to enter homes in large numbers, drawn by lights and seeking shelter. If you’re finding earwigs indoors during midsummer, your garden populations are high enough to warrant attention outside.
The Upside of Earwigs
Before waging all-out war, it’s worth knowing that earwigs are omnivores. They eat aphids, mites, and insect eggs alongside your plants. In a garden where aphid pressure is high, a moderate earwig population may actually be doing more good than harm. The damage becomes a problem when earwig numbers spike and they shift heavily toward plant feeding, which usually happens when populations outgrow their insect prey. The goal for most gardeners is population reduction, not total elimination.
Trapping: What Actually Works
Oil traps are the most effective DIY method. Fill a small container with a fishy-smelling oil (tuna oil, sardine oil, or smoked oyster oil all work well) and bury it so the rim sits level with the soil surface. In field testing by The Old Farmer’s Almanac, this style of trap caught about a dozen earwigs in a single night, far outperforming every other homemade option tested.
Canola oil also works, and some gardeners boost its appeal by mixing in bacon grease or hamburger fat. Earwigs are drawn to greasy, oily substances. Adding a lid with a small entry hole cut into it helps keep the trap selective, since other insects generally ignore the oil. Empty and refill the traps weekly.
Several popular trap designs performed poorly in the same tests. A soy sauce and oil mixture in a lidded container mostly attracted ants. A toilet paper tube stuffed with straw caught a single earwig. A can of leftover beer caught nothing. A crumpled damp newspaper in an inverted flowerpot also caught nothing. These methods show up frequently in gardening advice, but the oil-only trap outperformed them all by a wide margin.
Other Control Strategies
Reducing hiding spots is the simplest long-term approach. Earwigs spend the day tucked under mulch, boards, stones, leaf litter, and ground-level debris. Thinning out excessive mulch near vulnerable plants, clearing garden debris, and improving air circulation around beds makes the area less hospitable. Watering in the morning rather than the evening also helps, since earwigs prefer damp surfaces at night.
Diatomaceous earth, the food-grade form, can be dusted around the base of plants. It damages the waxy coating on earwig bodies and causes dehydration. It works best in dry conditions and needs to be reapplied after rain or irrigation.
For serious infestations, bait products containing spinosad (a naturally derived insecticide) are available at most garden centers. These baits target earwigs specifically when scattered around plant bases in the evening. Because earwigs feed at night, evening application puts the bait in their path when they’re most active. Spinosad breaks down relatively quickly in sunlight, so timing matters.
Physical barriers can protect individual high-value plants. Placing copper tape around raised bed edges or using cloches over young seedlings during the first few weeks after transplanting gives vulnerable plants time to establish before earwig season hits full force in July.