Q: Help! Earwigs are eating my plants. Plus they're gross! What can I do about them?
I’m not a squeamish gardener. I have a genuine interest in insects of all sorts and I am not afraid to squish slugs, aphids and caterpillars with my bare hands if there is nothing else available. But there is something about earwigs that gives me the willies. They’re like a creature out of a vintage horror movie in miniature form! Shudder.
Despite their gruesome appearance, earwigs (Forficula auricularia) aren’t all bad. Before I moved to a new garden I enjoyed a peaceful coexistence with these sometimes beneficial omnivores. When populations are balanced, earwigs root about in moist areas of the garden gobbling up slugs, snails and other destructive garden pests and feasting on decaying plant matter. They are one of nature’s natural composters! It’s only when there is a population bloom — sometimes caused by a particularly wet or mild season, or a proliferation of their favorite botanical treats (dahlias, marigolds, squash, potatoes and beans to name a few) – that they become a real menace. Next to slugs and snails, earwigs now rank as my garden's #2 threat.
If your garden is close to home, head out at night with a flashlight, checking underneath foliage and in the nooks and crannies between the stems and leaves of plants. Other nocturnal eaters such as caterpillars, slugs and snails leave behind a similar pattern of damage; sometimes earwigs are actually doing us a favor by feasting on these pests, and end up taking the rap (rather unfairly) for their misdeeds.
However, if you are like me and regularly harvest lettuce heads and zucchini flowers that are teaming with the squirmy little monsters then here’s what you can do to bring the enemy down.
One of the best ways to reduce the earwig population without upsetting your garden’s ecology is through the use of non-invasive traps. Earwigs love moisture. They forage through moist areas at night and bed down in them throughout the day. Crumple a few pages of lightly moistened newspaper into a loose wad or roll them up into a tube. Install these traps before nightfall and collect them the next morning. Don’t unroll or unravel to look inside. Make quick work of it by grabbing the newspaper and dumping it quickly into an empty, deep bucket. Do the entire garden this way and then fill up the bucket with hot, soapy water to drown the earwigs that were nestled inside. You can stomp on the traps instead if it makes you feel better. You can also try smearing on a little oil or bacon grease before setting out the traps – they won’t be able to resist it, but then again neither will other unwelcome guests so I advise skipping this step if you live in an urban area prone to vermin.
Oil and bacon fat can also be used in a way similar to how you would trap slugs and snails. You might even get a two-for-one special this way. Sink a deep container half-full of soapy water into the ground underneath a tree or plant where earwigs have been enjoying a nightly meal. Make sure it is buried at ground level so that they can crawl right in. Smear a little oil inside the container just underneath the rim, or add a few drops to the soapy water. The earwigs will rush inside and drown in the water. Change the traps daily as they will fill up quickly at first.
I’m not a big fan of the finely powdered fossil dust known as diatomaceous earth, as it can do a nasty number on our insides if accidentally inhaled. Still, it does take earwigs and other garden pests to task by scratching the soft parts of their bodies, causing them to die of dehydration. Using caution, sprinkle the powder in a protective ring around the base of plants. You’ll need to pull back any mulch first, and reapply every time it rains.
Garden authority Gayla Trail is the creator of YouGrowGirl.com.