How to make the (nearly) perfect fruit fly trap

From time to time, even the best of us are plagued with unwanted house guests. There is one type of flying insect that is particularly obnoxious, and difficult to get rid of — fruit flies.

These are tiny, gnat-like insects that are drawn to overripe fruit, wine, vinegar, and many other household foods. For the longest time, I thought they were just gnats, but they are a completely different family of insects. They can most often be found around, you guessed it, fruit. They also tend to congregate around kitchen trash cans, sinks, and sometimes bathrooms.

One of the main reasons these tiny pests are so difficult to get rid of is their short lifespans (and ergo, fast breeding cycles). Females can reach breeding maturity 8 hours after emergence from the larvae stage — and I thought human kids were growing up too fast these days. And they can lay as many as 2000 eggs in their short lifetime.

Onto the trap.

This is a very simple trap to make, and uses only safe, household items. Here’s what you’ll need:

  • a pickle jar (or similar)
  • a nail or ice pick
  • petroleum jelly
  • balsamic vinegar (though other food vinegars should work)
  • dish soap

Clean out your pickle jar and make 8–12 small holes in the lid using your nail and hammer, or an ice pick. These holes must be large enough for the flies to crawl through — making the holes too small will render your trap ineffective. Go for about the size of the holes on your salt shaker.

Next place a half-inch or so of balsamic vinegar into the the jar. Squeeze a couple of drops of dish soap into the vinegar and swirl it around. The dish soap will break the surface tension of the vinegar (causing the flies to be submerged and meet their end in a more timely fashion).

Next use your finger to create a line of petroleum jelly around the underside edge of the lid. This will create a sticky barrier that prevents the fruit flies from crawling back onto the lid and finding their freedom.

That’s it — put the lid on and enjoy your sense of accomplishment. Fruit flies find vinegar irresistible and will immediately be drawn to the scent. If you have a lot of them in the house, you’ll see results within hours, if not minutes.