Q. Mike: We have a HUGE, persistent problem with earwigs. They are in the garden, around the house, in the flowerbeds, under every rock and even the birdbath. And they eat everything! My wife has tried several natural deterrents with no luck and is thinking of using chemicals out of frustration. Do you have any suggestions?
- ---John in Leelanau County, Michigan (just north of Traverse City)
Mike: Your website is awesome and full of great advice, but nothing about earwigs! Can you please recommend anything that may work? They are almost impossible to get rid of, and along with the squirrels, are making a mess of our garden. Thank you!
- ---Nicky; in southern Ontario, Canada
Michael, you were blowing it out [the wrong end] when you said a few weeks back that earwigs aren't important garden pests. They are a big problem here, clipping the silks off my sweet corn and preventing my dahlias from blooming! They appear in damp towels left on the kitchen counter and I even found one in a connection box up on the roof!
- ---Michael in grand Traverse county Michigan
Mike: What can I do to get rid of earwigs? At first I thought it was a grub problem, and used Escar-Go, but my marigolds and clematis are still being eaten to nubs, and earwigs are everywhere!
- ---Jan; Chicago, Illinois
A. I'm glad that Jan in Chicago mentioned "Escar-Go". That's the brand name of an iron phosphate bait sold to control slugs (who can't metabolize iron). It has no effect on grubs, the underground larvae of plant-eating beetles. (And grubs don't eat above-ground plant parts, so we presume Jan meant to say slugs.)
But her typo did provide valuable information, as I strongly feel that late night raids of slimy slugs are often the actual cause of damage wrongly attributed to earwigs, and my first 'earwig suggestion' is always to get your slugs under control and see if there's still a problem once the slimers have been dispatched. It looks that that's not the case for Jan, however, as the Escar-Go bait would have ended her problems if slugs were to blame.
But in an odd twist of good news, an improved version of these iron phosphate products has JUST hit the market that DOES control earwigs (and cutworms, pill bugs and sow bugs in addition to the original slugs). Sold under brand names like "Escar-Go Supreme" and "Sluggo Plus", a natural, bacteria-based spinosad has been added to the original iron phosphate formula. Spinosads have been around for a while now—they're a great organic control for fire ants—and I like them a lot. Together with an attractive bait and that slug-stopping iron phosphate, they should be great at controlling lots of ground level pests. In fact, I consider these 'next generation' iron phosphate products to be the modern weapon of choice against earwigs.
Now, before we get to your other control options, a little mea culpa time: This is isn't the first time I've been called on the earwig carpet. Back when I was Editor of ORGANIC GARDENING magazine, I wrote (echoing the advice of several entomologists) that earwigs were generally harmless creatures, and were considered to be so beneficial in orchards that captured garden earwigs were often released into fruit trees to control aphids, spider mites, various 'fruit worms' and other pests. Our readers responded with so many tales of woe that I finally had to recant. (By the way, "Michigan Mike" is also right on with his flower complaint; an entomologist who helped with our recantation back then specified their preference for devastating dahlias.)
Anyway, like slugs, earwigs are nocturnal moisture lovers, and controlling moisture in your garden is the first step in limiting the activity of both (and sow bugs and pill bugs and possibly some other pests I'm not thinking of right now.) So pull back any mulch near affected plants and only water your garden in the morning; to keep night time moistness at a minimum.
Then become a trapper. Like slugs, earwigs will crawl under any moist surface when the sun comes up, so leave thick sections of newspaper out in the garden overnight, and in the morning, shake the earwigs hiding underneath into a container with a couple inches of soapy water in the bottom. Specialized boards may be even better; Canadian entomologists found that traps made of boards with deep grooves cut into the undersides of the wood worked as well as toxic pesticides! Either way, keep the rest of the garden dry but wet down the 'trap areas' in the evening to maximize your catch.
Earwigs also love to hide inside small round things, so cut a leaky old hose into sections a foot or two long, and leave these out in the garden overnight. In the morning, dump the enclosed earwigs into that soapy water (or onto your fruit trees). You could also dust the area around affected plants with diatomaceous earth. Made from the fossilized remains of ancient sea-going diatoms, this fine powder dehydrates moisture-loving pests like slugs, earwigs and cock-a-roaches.
One of many OG readers responding to my 'hey, they're not so bad' statement back in the 90s, said that making his garden toad friendly completely ended his earwig problems. He even had his toad scat analyzed as confirmation; filled with earwig exoskeletons, was the report. All you need to do to attract these amphibious earwig-eaters is to have birdbath saucers set into the ground in the center of the garden (filled with water of course) for them to frolic in, and damp shady spots for them to hide in during the day.
Another California reader reported great success using beer traps against earwigs. Fill some old margarine tubs with an inch or two of fresh beer at sundown, and place them around the affected plants. Because beer traps also work well at drowning slugs, you'll get revenge and a positive pest ID in the morning. (Other sources insist vegetable oil traps are much better for earwig control.)
As with any other roving piece of protein, earwigs are food for other creatures, including an excellent beneficial insect called the tachnid fly. You can attract these helpful flies to your garden by growing Shasta daisies, clovers, yarrow, parsley, fennel and many other herbs—but you must let the herbs bloom, as the flies are attracted to the pollen in those flowers. The online encyclopedia Wikipedia adds that earwigs can also be controlled by spraying beneficial nematodes in your garden; seems that the microscopic nematodes attack the larval stage of the pest.
And finally, to keep them out of your house (in deference to keeping the insect fear factor at a minimum here, I will not repeat the many places our OG readers found these creatures indoors) keep the air as dry as possible with dehumidifiers and air conditioners; this will also keep mold and millipede problems at a minimum. You can also dust some diatomaceous earth around likely points of entry. And like our clever listener Michigan Mike, you can leave damp kitchen towels out overnight to capture them in.
Oh, and always sleep with earplugs.