Q: Although we’re experiencing some winter weather, the temperatures in my neck of the woods have been pretty erratic — in the high 60s one day and in the low 40s the next. In addition to throwing off my morning outfit planning, the wild temperature swings have rendered my home, specifically my kitchen, a haven for some pretty confused fruit flies that vanish when the temps climb and then, most annoyingly, reappear when it gets chilly. Obviously, I can’t control what the weather does from one day to the next, but I would like to get a handle on these winged pests when they come indoors seeking warmth —  running around with a fly swatter has become tiresome. Have any thoughts on how to prevent and trap or kill ‘em in a non-grisly, chemical- and swat-free manner?

A: Funny you ask … I’ve been noticing the exact same thing in my own apartment. When the temperature dips, a few (I’m lucky, as fruit fly problems can get real bad) rather clumsy fruit flies will appear buzzing around my sink and kitchen countertops and then, when it’s toasty out a couple days later, they’ve vamoosed.

Not to make any assumptions about your housekeeping habits but, as you probably know, the cleaner the home, the less attractive it will be to your unwanted, bacteria-laden houseguests who are probably sneaking in through open windows or cracks, crannies and crevices in your home — either that or they’re hitching a ride on the fruit and veggies that you’re bringing home from the market or your garden. So wash that produce well, take out the trash and compost pail and clean house with a vengeance, paying mind to kitchen surfaces along with drains and garbage disposals.

If you’ve cleaned your kitchen top to bottom — it doesn’t hurt to scour other areas of the home as well — and the rapidly multiplying flies keep a-comin’ back for more, it’s time to grab the vinegar. And no, I’m not referring to the multipurpose miracle worker known as white vinegar, but apple cider, balsamic or red wine vinegar. Flies love the stuff (it’s fermented after all), so when used correctly you can trap or kill them quite effectively and with less exhausting frustration than a swatter, less of a sticky mess than flypaper and less energy than a vacuum cleaner or, gasp, hair dryer.

Perhaps the most effective way of using vinegar to your fly-trapping advantage is to pour a bit — an inch or so — in a Mason jar and stick a tight paper cone in it, pointed end placed downward, so that it’s not quite touching the vinegar. Fruit flies will smell the delightful aroma of the vinegar (strategic placement is key here … place the funnel trap near where they’ve been congregating) and travel straight into the cone where they’ll become trapped and meet a vinegar-y end. A non-death-by-drowning variation of the “cone method” involves placing a rotted piece of fruit in a jar as bait. Like with the vinegar trick, they’ll fly through the paper funnel and become trapped in the jar, unable to fly back out. Once you’ve collected a few, you can take the jar outside and release them as you see fit.

A more straightforward, non-catch-and-release approach is to simply leave out shallow bowls of liquid dish soap mixed with a splash of vinegar. Or, if you enjoy a glass of wine or bottle of beer with dinner, leave ‘em out overnight to see if they attract any winged imbibers. Either way, they’ll most likely drown. In the past, I’ve even experimented with putting a mixture of dish soap and balsamic in an empty plastic water bottle and leaving it out on my kitchen counter. Although it didn’t work wonders, this method did manage to snare a few doomed souls. I’m also pretty vigilant about taking preventive measures like cleaning the drain of my kitchen sink (white vinegar and baking soda chased with hot water), wiping down my indoor recycling can and replacing old sponges and dish towels.

I hope this helps and if you come across any other methods, please do let me know!

— Matt

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Photo: mschmidt62/Flickr

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Matt Hickman ( @mattyhick ) writes about design, architecture and the intersection between the natural world and the built environment.