June 15, 2006

Fighting earwigs

One day about 20 years ago, my husband came back from buying pesticide and announced, "The guy at the store said earwigs will arrive next year." Huh? Well, "the guy" was right. Apparently these little darlings got off a ship from Japan and worked their way slowly across the continent. The next year I saw my first earwig, and although I'm not particularly squeamish about bugs, it grossed me out. Familiarity breeds contempt, as they say, and I'm no longer grossed out by them (OK, just a little), but they certainly don't inspire affection. They are on the extremely short list of things that I can kill without the slightest twinge of remorse. (For those of you who are unhealthily curious, houseflies, mosquitoes and lily beetles are the rest of the list. I even feel sorry for slugs, if you can imagine it.)

Now a variety of experts will insist that earwigs feed on decaying vegetable matter and aphids and are therefore beneficial. They are probably right most of the time. But if earwigs are short of the appropriate decaying materials, or if temptation is just too strong, they are only too happy to reduce any tender foliage and a number of flowers to lace. I wish I'd had an expert with me the night I went out to do battle with the slugs that were eating my baby marigolds down to a stub and found them covered in earwigs instead. They are also fond of coleus, salvia, nasturtiums (especially the flowers), monkshood flowers, pepper plants (not deterred by hot ones) and just about anything with thin enough leaves. And this is a list just from my personal experience.

There are several ways of dealing with earwigs. I generally ignore them until they start causing damage, because in small numbers they don't do enough harm to bother with them. But when I find leaves reduced to lace, I take action.

Earwig patrol: I go out around 10:00 at night with a flashlight and a one litre spray bottle filled with a 10% ammonia solution plus a teaspoon of dish detergent. I do the rounds of damaged plants, spraying any earwigs and slugs I find. The ammonia kills the slugs on contact, and the soap will kill the earwigs within a few minutes. I'm inclined to believe that they leave some kind of chemical trail like ants, because if I do the rounds a second time, I will find a fresh crop of earwigs chomping in the identical places, right down to the precise leaf. You can also do this with a bowl of soapy water and knock both slugs and earwigs into them, but that requires three hands or a willing partner in pest hunting, both of which tend to be in short supply for me. A flashlight mounted on a hard hat would help, but the neighbours think I'm weird enough already.

Diatomaceous earth: I sprinkle this anywhere I'm reasonably sure the earwigs will be crawling, with my favourite place being under potted plants on the patio where they will often hide out in the daytime.

Traps: The easiest that I know of, (and as you may have noticed, I am a great fan of easy) is to partially sink a shallow container, like a tuna can, in the soil, with a layer of soya sauce and a layer of cooking oil. The smell of the soya sauce apparently attracts them and the cooking oil makes it impossible for them to get out and probably smothers them. Anyway, if I've got an earwig infestation going on, it will be full of dead earwigs in the morning.

The Earwig Stomp: Put on your favourite dance music (optional) and stomp on them as they skitter across the patio or sidewalk. You won't get great numbers this way, but it's emotionally satisfying and burns off calories. Do wear shoes...

21 comments:

Miss Canthus said...

We had earwigs in the orchards in BC when I was young. They hung out inside peaches and apricots. There is nothing quite as unpleasant as seeing an earwig crawl out of a piece of fruit you about to sink your teeth into!

They also get into a cob of corn, while it is still on the plant. They eat the kernels.

So to these so-called experts who say they only eat decaying material I say "Phooey!!"

Beth in Madison, WI said...

Thanks so much for the info ! We are having a wet summer here, and the earwigs are prolific. I didn't realize they could be so destructive...I'll be out tonight with my flashlight and spraybottle !!

Cowells said...

Thanks for this post; I feel like the tide has turned in this war. Amazing what a little soapy spray and some soy/oil traps can accomplish!

Janet said...

It does take some diligence, but a consistent attack brings the numbers down to reasonable levels. I'm not the best at being consistent, which is why I'm particularly fond of the soya sauce traps. ;o) But I'm getting out several nights a week now with the spray bottle, and things are starting to turn around. Should have started six weeks ago.

Sigrun said...

Janet, I have learned a new word today: Earwigs - Ohrenkriecher! ;-)

Sigrun

Janet said...

Eww! Just as ugly in German as in English! So now I've learned a new word too.

Anonymous said...

hey, I just wanted to know if the ammonia soultion used on earwigs harms good plants.

Thanks for your time

Signed
The young gardener

Mary in Idaho said...

My garden is still pretty young and seeing earwigs on my young roses is disgusting. I really dislike the little buggers. I have read numerous other articles about the oil method. The soapy water sounds like a great idea as well. I will have to try them both. I guess there is no way to really just get rid of them. Thank you for all the wonderful ideas. Good luck everyone!!!

Janet said...

Mary, it's always a good idea to fight persistent pests with several methods, preferably ones that don't introduce toxins into the environment.

But like I said, it's probably not worth fighting too hard if they aren't creating damage.

After a mild winter and a cool damp spring, it's good to be more aggressive. Those conditions favour both slugs and earwigs and spring is a good time to get them, before they've had a chance to reproduce too much. A good cold winter (a week of -20 Celsius does the trick) usually knocks them back so far you don't have to worry too much the following spring. 2007-2008 was such a winter for us here, and I've had little trouble this year.

Anonymous said...

I thought it was the rabbits that live in my yard eating everything. It was earwigs! Oh I bet they're freakin' everywhere when I turn off the light!! How disgusting, I'm gonna set up 25 of those tuna cans tomorrow. Wish me luck.

Janet said...

25? It's a safe bet your garden is bigger than mine. Good luck!

Anonymous said...

The soy and oil traps worked amazingly!

Janet Ursel said...

Anon, I am glad to hear it. The only thing to watch for is rain splashing the mixture onto surrounding plants.

Anonymous said...

Oh my goodness, this is all so very helpful, thank you! Question however- 10% ammonia and tsp. dish detergent. Is the other 90% water then?

Holly In Wisconsin said...

I think their are a million of these horrible little creatures in my hanging flower baskets! And now they are trying to get into the house. It is full scale war here. I've been doing the tuna can thing, only with mollasses instead of soy sauce. It works, but I'd need a hundred of them. And Dawn in my spray bottle kills them off as I see them out of my plants. My question is, will dish soap srayed onto my plants harm them? Waht if it gets in to soil?

Anonymous said...

thank you so much for your post. I will get on those recommendations tonight for sure..PS i've been stomping away already, we are infested this year and they are discusting..We also have slugs, and i feel bad for killing them as well..One other method for slugs if i may suggest to all of you, is put some cornmeal in a glass jar, tilt the jar on the side in the garden and when you go out at about 10 ish, you should see them munching on the corn meal, it bloats them and they die off, and it is harmless to pets...

Janet Ursel said...

Sorry for the late replies; I've been having health problems and a lot of things are getting neglected.

Anonymous June 18: Yes, the other 90% is water.

Holly, different plants have different sensitivities to getting soap on their leaves. Normally a little won't hurt. And the little that will drip down to the soil isn't likely to cause problems. You basically have to drench a root system in soapy water to harm a plant. Don't ask how I know...

Anonymous June 23, cornmeal is indeed great in the garden. It's supposed to be good against pillbugs and sowbugs too.

Cliff said...

Hello Janet.
Well I finally put a garden in this year after 7 years. I chose an area near my detatched garage as i like the water runoff from the roof. It seems so do the earwigs. They were relentless for weeks. I tried everything, until i came across your blog and tried the soy sauce and vegetable oil trick.
I used one well cleaned tuna can with a thin layer of soy, then filled half way with used frying oil from my chicken fryer.
Much to my amusement, i checked it this morning, and the can was filled to the brim with earwigs!! You saved my garden, and my sanity!! Thank you Thank you Thank you!.

Anonymous said...

My husband said to sprinkle the diatomaceous earth all over the plant but another website said to put it on the ground around the base of the plant. Will the diatomaceous earth hurt the plant or the blooms if sprayed directly on them?

Anonymous said...

Can diatomaceous earth hurt plants if sprayed directly on blooms and leaves

mistyjive said...

Thank you so much for this info! I am waging a full scale war here with these creatures. They are in every flower bed, potted plant, dark corner, and under every cushion on my deck. Needless to say, they are working their way into my house! I will be putting a ton of the buried cans all around my yard to put a stop to their hungry little ways. They have already ruined one new plant I just planted this year and are destroying my sage plants. They are also ruining my outdoor enjoyment! I can't wait to get started on getting their numbers out of control!!