Earwigs

by Laura Willett, Master Gardener

Master Gardeners had many discussions with Farmer’s Market shoppers at the Rotary Pavilion this week about EARWIGS!  They seem to be very abundant in Yakima gardens this year.

Earwig on a leaf
Earwig

Though an old European myth claims they burrow into human brains via the ear while the victim is sleeping, earwigs are harmless to humans.  In fact, earwigs can be beneficial predators in your garden, eating soft bodied insects like aphids, mites and insect larvae.  They are also vital scavengers that break down decaying organic matter, enriching your soil in the process.  But they can also be garden pests that chew holes in seedlings, flowers, and soft fruits.  

While earwigs look intimidating to gardeners, they use those forceps-like pincers for defense and capturing prey.  While harmless to humans, earwigs can cause visible damage to Yakima gardens. 

  • Appearance: They are about 3/4-inch long, dark brown, and have visible pincers at the tail end. Females have mostly straight pincers, while a male’s pincers are larger and more distinctly curved
  • Signs of Damage: They chew irregular holes in leaves, petals, and fruit. Damage is very similar to slugs, but earwigs do not leave a telltale slime trail.
  • Favorite Targets: They love seedlings, soft fruits (strawberries, apricots, and peaches), sweet corn, and flowers like marigolds and dahlias.

How to Control and Manage Earwigs

Remove Hiding Places

  • Earwigs thrive in dark, damp environments during the day. 
  • Clear away excess mulch, leaf litter, and garden debris near your plant beds
  • Move boards, stones, and unused pots away from the base of your plants.
  • Prune the lower leaves of leafy vegetables (like cabbage or broccoli) so they don’t rest on the soil. 

Adjust Your Watering Schedule

  • Because earwigs love cool, moist soil, you can make your garden unappealing by changing how you water. 
  • Water deeply, but less often.
  • Water in the morning. This allows the surface of the soil to dry out before nightfall when earwigs become active. 

Set DIY Traps

  • Submerged Trap: make a pungent trap with oil and bacon grease or tuna fish oil in a small, shallow container like a tuna fish can. Bury it so the rim is level with the soil. The earwigs will crawl in and drown. 
  • Rolled Newspaper Trap: dampen a newspaper or magazine, roll it up and secure with rubber band, and place it in the garden in the evening. By morning, earwigs will crawl inside to hide. You can then shake out the earwigs into soapy water to drown, or simply destroy the paper trap. 

For further reading on controlling earwigs on specific crops, check out this Fact Sheet from WSU’s Hortsense. 

Remember, if you are not seeing damage, you might want to let the earwigs continue to control other insect pests in your garden.