Earwigs in Southern California Gardens: Should You Be Worried?

Almost nobody calls about earwigs because of damage. They call because they moved a potted plant, found something reddish-brown with a pair of forceps on its back end, and had a visceral reaction — and then, somewhere in the back of their mind, remembered a story about ears. The insect is genuinely unsettling to look at. Almost everything people believe about it is wrong, and the truthful version is more interesting than the myth.

Earwigs are unmistakable once you know the profile. Adults run roughly half an inch to three quarters of an inch, with a flattened, elongated, segmented body in reddish-brown to nearly black, and slender antennae about half the body length. The defining feature is at the back: a pair of curved pincer-like appendages called cerci.

The cerci are worth a closer look because they tell you the sex. Males have pronounced, strongly curved pincers; females have straighter, more slender ones. It is one of the more easily observed differences in a common insect, and it is a good way to make a child less frightened of one — turning it into something to examine rather than something to flee.

Most species have wings folded under short leathery wing covers, and while many can technically fly, they very rarely do, so you will almost always see them running. And they run — quickly, and toward cover, which combined with the pincers is most of why people find them alarming.

The species you are most likely to encounter here is the European earwig, which is established throughout California and thoroughly at home in irrigated Southern California landscaping.

It is worth addressing head-on rather than skipping past, because it is one of the most searched questions about any insect and because a lot of people carry a genuine low-grade dread about it.

Earwigs do not crawl into ears to lay eggs, burrow into brains, or anything adjacent to that. The story is old European folklore, reflected in the name in several languages, and it predates any real understanding of the insect. There is no behavioral basis for it: earwigs seek dark, damp, tight spaces, and while essentially any small insect can end up in an ear canal by accident — this happens occasionally with a variety of insects and is not specific to earwigs — there is nothing about them that makes it a tendency.

They also do not lay eggs in people or animals. Earwigs are among the relatively few insects that show genuine maternal care: a female lays her eggs in a burrow in soil and then stays with them, cleaning them to prevent fungal growth and guarding the young after they hatch. It is a legitimately unusual behavior in the insect world and considerably more interesting than the myth.

Earwigs are nocturnal and strongly moisture-dependent, and everything about where you find them follows from those two facts. They spend daylight hours in dark, damp, tight spaces and come out at night to feed.

The important thing to understand about the indoor appearances: earwigs are accidental invaders. They do not establish breeding populations inside houses the way cockroaches and ants do, and an earwig in your bathroom came in from outside rather than emerging from an indoor colony. That is why the fix is almost entirely about the perimeter and the moisture rather than anything applied indoors.

This is where earwigs deserve a more honest treatment than they usually get, because they are one of the clearer cases of an insect that is not straightforwardly a pest.

On the damage side: in sufficient numbers they chew irregular holes in leaves and flower petals, and they can do real harm to seedlings and young transplants, which are tender enough that a few nights of feeding sets them back or kills them. They also feed on soft fruit — strawberries, stone fruit, and berries — and on the silk of sweet corn. Their feeding damage is ragged and irregular, which distinguishes it from the cleaner cuts of caterpillars or the skeletonizing pattern of some beetles. Seedling beds and soft fruit are where a gardener genuinely has cause to act.

On the beneficial side, which is the part that gets left out: earwigs are omnivores and a meaningful part of their diet is other invertebrates. They prey on aphids, mites, insect eggs, and small larvae, and there is genuine agricultural research treating them as beneficial predators in some tree crops. They also consume decaying plant matter, contributing to the breakdown of organic material in a garden bed.

So the sensible posture is threshold-based rather than eliminationist. A handful of earwigs in mulch is part of a functioning garden and probably doing you more good than harm. Enough of them to visibly damage seedlings or fruit is a problem worth addressing — and the honest reason to address it is the specific damage, not the insect existing.

Cultural changes do most of the work. Pull mulch back a few inches from plant stems and the foundation, since the mulch is the harborage rather than the plants. Clear leaf litter and garden debris where you can. Water in the morning rather than the evening so beds are drier overnight when earwigs are active. Lift pots onto feet so the damp ring underneath goes away. Protect seedlings specifically — they are the vulnerable stage, and collars or covers over a few weeks get transplants past it.

The classic low-effort trap works genuinely well and is worth knowing: a rolled-up damp newspaper, a short length of old hose, or a shallow container of oil left in the bed overnight. They gather in it by morning and can be disposed of. It is a decent way to gauge how many you actually have before deciding whether you have a problem at all.

An occasional earwig indoors needs nothing beyond a tissue. The situations that warrant more:

That last point is the genuinely useful one. Earwigs indoors are best read as a moisture and entry-point diagnostic. The reason to act is not that earwigs are dangerous — they are not — but that sustained dampness in a subarea or against a foundation is the precondition for problems that are considerably more expensive, subterranean termites and wood-decay fungus among them. An earwig is a cheap early warning.

The work itself, where it is warranted, is perimeter-focused: treating and sealing at ground level where they are entering, addressing the harborage in mulch and debris against the structure, and identifying the moisture condition. Broadcast interior treatment is not the answer for an insect that is not breeding indoors.