Yes, Sevin kills earwigs. It’s one of the most commonly recommended insecticides for earwig control, available in spray, granule, and dust formulations that work on contact. Utah State University Extension lists it among the effective chemical options for homeowners dealing with earwig problems.
How Sevin Kills Earwigs
Most current Sevin products for home use contain a pyrethroid insecticide that attacks the earwig’s nervous system. Normally, insect muscles rely on tiny channels that open and close to control movement. The active ingredient jams those channels open, locking the insect’s muscles in a state of constant firing. The earwig loses the ability to move normally and dies from overstimulation.
It’s worth knowing that Sevin’s formula has changed in recent years. The brand was long synonymous with carbaryl, but many consumer products, including Sevin Insect Killer sprays and Sevin Lawn Granules, now use zeta-cypermethrin instead. The dust formulation (Sevin 5% Dust) may still contain the original carbaryl, though remaining carbaryl stock is gradually being replaced. Both active ingredients kill earwigs, but the newer pyrethroid formula offers some practical advantages, particularly shorter waiting periods before harvesting edible crops.
Which Sevin Formulation to Use
Sevin comes in several forms, and the right one depends on where your earwig problem is and how large the area is.
- Ready-to-Use Spray: Best for spot-treating small garden areas or individual plants. The adjustable nozzle lets you switch between a focused stream and a wider spray pattern.
- Lawn Granules: Designed for broader coverage across lawns, garden beds, and perimeter areas around your home. Spread them with a standard lawn spreader, then water immediately. The moisture activates the product so it kills earwigs on contact.
- Concentrate: More economical for covering larger areas like garden beds, small trees, shrubs, and home foundations up to 3 feet high. Mix it in a pump sprayer and coat surfaces thoroughly, including damp mulch where earwigs like to hide.
- Hose-End Spray: Attaches directly to your garden hose and mixes automatically. Good for treating lawns, gardens, and foundation perimeters without the hassle of a separate sprayer.
Where and When to Apply
Earwigs are nocturnal and spend daylight hours tucked into moist, dark spots. Target those hiding places: damp leaf debris, garden mulch, areas under container plants and their saucers, foundation cracks, and the base of shrubs. For foundation treatments, apply up to 3 feet high and coat the surrounding ground where earwigs travel at night.
If you suspect earwigs are damaging your garden but haven’t actually seen them, go out after dark with a flashlight. You’ll catch them actively feeding on leaves and flowers, which confirms the problem and shows you exactly where to focus treatment. With granules, watering right after application is essential, not optional. The water releases the active ingredient into the soil surface where earwigs make contact.
Harvest Timing for Edible Gardens
If you’re treating vegetable or fruit gardens, the time you need to wait between spraying and harvesting depends on the formulation. The newer zeta-cypermethrin products have a one-day pre-harvest interval for most edible crops: tomatoes, peppers, okra, squash, melons, broccoli, lettuce, greens, beans, peas, and root vegetables like potatoes and turnips. That’s a significant improvement over the older carbaryl formula, which required 3 to 14 days depending on the crop. Some crops like corn, peanuts, and sunflowers still have longer waiting periods, so check the product label for your specific plants.
Downsides to Consider
Sevin is a broad-spectrum insecticide, meaning it doesn’t just kill earwigs. It can also harm beneficial insects, including the natural predators that help keep earwig populations in check. Pollinators like bees are vulnerable too. This creates a tradeoff: you’ll get quick knockdown of earwigs, but you may also disrupt the natural balance that was partially controlling them.
Non-Chemical Methods That Work
Trapping is surprisingly effective against earwigs and can reduce populations to manageable levels without chemicals. The University of California IPM program recommends a simple oil trap: fill a low-sided can (like a tuna or cat food tin) with half an inch of vegetable oil and a drop of bacon grease or fish oil. Place several of these around your yard near ground cover, fences, and garden beds. Earwigs are strongly attracted to fish oil and will crawl in and drown. Empty and refill traps daily.
Rolled-up newspapers, short lengths of garden hose, or bamboo tubes also work as traps. Set them on the soil near affected plants before dark. In the morning, shake the earwigs that crawled inside overnight into a bucket of soapy water. Daily trapping sounds tedious, but it genuinely works if you stick with it.
Habitat modification matters just as much. Earwigs need moisture and hiding spots to survive, so reducing both makes your yard less hospitable. Clear away leaf litter, dense ground cover, and debris near garden beds and foundations. Fix leaky faucets and downspouts. Switch to drip irrigation where possible instead of overhead watering. Move potted plants away from problem areas. If earwigs are climbing fruit trees, a band of sticky barrier product around the trunk stops them, and harvesting fruit as soon as it ripens gives them less opportunity to feed.
Chickens, ducks, toads, and birds are natural earwig predators and can make a noticeable dent in populations if your yard supports them.