A pest control expert shares his best advice.
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Drain and fruit flies are two nuisance pests commonly found indoors. And while they have similarities—both are small compared to larger house flies and breed in organic materials—their respective infestations require different treatment plans. Here, Jim Fredericks, Ph.D., a chief entomologist for the National Pest Management Association (NPMA), explains how you can identify and exterminate these common bugs for good.

Drain Flies

Drain flies, which are sometimes also known as moth flies, breed in the organic debris that builds up—as their name implies—inside of drains. "The larvae burrow into and feed on the gelatinous goo that lines drains," says Fredericks. "They are often seen resting on vertical surfaces but will fly when disturbed." Drain flies are most commonly confused with the phorid species, which is more nefarious; an infestation of this bug is most often associated with a broken sewage pipe that has contaminated the soil that surrounds it. "The flies' larvae feed in this soil, and will often emerge back through the drains that lead to these pipes," he says, adding that another name for these are coffin and mausoleum flies, since they thrive in a variety of decaying organic materials.

Fruit Flies

Fruit flies, similarly, are commonly found in homes, restaurants, and other facilities where food is processed, says Fredericks. "They are typically tan and have red eyes," he says, adding that you'll find them hovering over too-ripe fruits and vegetables. "The flies lay eggs on overripe fruits and veggies and their larvae feed on the yeast cells that are produced as the produce ferments," he says. It is the fermentation process that attracts them—which is why it's not uncommon to see fruit flies at wineries, circling your wine glass.

fruit bowl
Credit: Getty / nitrub

Exterminating Both Species

"Fly identification is the critical first step in the control process," affirms Fredericks. "You need to know which fly is causing the infestation, so that the breeding source can be addressed." You can control fruit flies by eliminating their food source and improve sanitation—"monitor produce that is left on the counter to ripen, and move it to the fridge before it goes bad," he shares. "And be aware of produce that is placed in garbage cans." Since flies will readily use trash cans as a food source, it's a good idea to choose a model with tightly-closed lid; clean your bin regularly to remove any organic materials left at the bottom. And don't forget to wipe up spills as soon as they happen, since it doesn't take much to attract and sustain fruit fly development, he adds.

As for drain flies? Extermination may be as simple as cleaning out your drain and sink trap. Removing phorid flies, on the other hand, is more challenging and may require a plumber and costly repairs to fix broken underground pipes. "It can be difficult for someone who is untrained to tell the difference between phorid flies and drain flies, so it is best to reach out to a professional for help," notes Fredericks.

Comments (32)

Martha Stewart Member
April 5, 2022
When we moved into our house, there were drain flies in the kitchen. I used 1/2 cup baking soda, 1/2 cup salt (mix and pour into drain) add 1 cup of white vinegar, let mixture work overnight. Flush in the morning with boiling water. Worked great!
Martha Stewart Member
February 28, 2022
Yeah.....no ideas here...unless it was to call a professional. Thanks Martha! NOT! I use Apple Cider Vinegar in a shallow bowl with a drop of dishwashing liquid. They flock to it and it kills those little buggers. I will use the Rice Wine Vinegar if I don't have Apple Cider in the future to see how this works out. Thanks for the suggestion. What I like about this solution? It is easy and cheap.
Martha Stewart Member
February 28, 2022
Yeah.....no ideas here...unless it was to call a professional. Thanks Martha! NOT! I use Apple Cider Vinegar in a shallow bowl with a drop of dishwashing liquid. They flock to it and it kills those little buggers. I will use the Rice Wine Vinegar if I don't have Apple Cider in the future to see how this works out. Thanks for the suggestion. What I like about this solution? It is easy and cheap.
Martha Stewart Member
June 21, 2021
I was looking for a solution. There were no tips here
Martha Stewart Member
May 20, 2021
Hydrogen Peroxide. I spray it on my plants' dirt and I've been enjoying sucess. Where ever those buggers show up, I spray. Just a little-just enough to change the chemistry of the surface.
Martha Stewart Member
May 17, 2021
I agree with the other commenters. I read through the article and kept waiting to read the solution in ridding myself of the little beasts but was told to contact a plumber or pest contractor. Wow, that is a no brained. Very disappointed.
Martha Stewart Member
May 17, 2021
I agree with the other commenters. I read through the article and kept waiting to read the solution in ridding myself of the little beasts but was told to contact a plumber or pest contractor. Wow, that is a no brained. Very disappointed.
Martha Stewart Member
May 17, 2021
Commercial fruit fly traps are pretty much just vinegar based. I just set out a custard size bowl (or saucer) of vinegar which attracts them. They usually get too close and their wings get wet and they drown. A sweeter vinegar works best for me, like rice vinegar, but try different vinegars to see which ones work best for your particular critters. Be sure to put it away from your other food, as fruit flies will congregate wherever your vinegar is and you don't want them jumping over to try out other foods you may have nearby.
Martha Stewart Member
May 17, 2021
A homemade trick that really works. Pour a small amount of apple cider vinegar into a container. Cover the top with plastic wrap. Poke small holes in the plastic. Set it on a counter in the area you see flies the most. I use a plastic water bottle cut down to about one inch. I secure the plastic wrap by putting a rubber band around the cup before poking the holes. It has always worked for me
Martha Stewart Member
May 17, 2021
A homemade trick that really works. Pour a small amount of apple cider vinegar into a container. Cover the top with plastic wrap. Poke small holes in the plastic. Set it on a counter in the area you see flies the most. I use a plastic water bottle cut down to about one inch. I secure the plastic wrap by putting a rubber band around the cup before poking the holes. It has always worked for me
Martha Stewart Member
May 17, 2021
A homemade trick that really works. Pour a small amount of apple cider vinegar into a container. Cover the top with plastic wrap. Poke small holes in the plastic. Set it on a counter in the area you see flies the most. I use a plastic water bottle cut down to about one inch. I secure the plastic wrap by putting a rubber band around the cup before poking the holes. It has always worked for me
Martha Stewart Member
May 17, 2021
Oh my gosh - totally useless. Waste of my time to read this article.
Martha Stewart Member
May 17, 2021
Oh my gosh - totally useless. Waste of my time to read this article.
Martha Stewart Member
May 17, 2021
I read how real cork will keep fruit flies away. Bought a beautiful bowl on Amazon made in France. Pricey but completely effective! I keep fruit out now in this beautiful bowl and have not seen one fruit fly. I should think you don't need this bowl, though, if you use real corks placed around your fruit in your own bowl. https://smile.amazon.com/gp/product/B07XRYNN5J/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
Martha Stewart Member
May 17, 2021
If I didn’t know, I would’ve thought my 3th grader may have written this article.... Copy and pasting a lot of info from other resources and not actually addressing the topic. . . I see she may have a career in writing. Thanks for the inspiration Lauren Wellbank.
Martha Stewart Member
May 17, 2021
I agree with all the posts. This is a totally useless article. To get rid of the fruit flies, at the FIRST sign of fruit flies in late spring or early summer you put out some small containers of wine or vinegar with a drop or two of dawn dishwashing liquid, then cover with plastic wrap and poke holes in the plastic, you will kill the fruit flies. It's gross to have a bunch of containers full of dead bugs on the counter but it's better than the live bugs. Just change it every day. This method will work if its later in the year but it's hard to get rid of them completely if you start late. I live in an apple orchard, this method does work.
Martha Stewart Member
May 9, 2021
I agree with every single thing that anonymous said! No help whatsoever!
Martha Stewart Member
May 4, 2021
Waste of time reading this. I already know what I have. Have gotten rid of food source -still have flies - needed to know how to kill them. This guy didn’t address that at all. Useless!!!!
Martha Stewart Member
May 4, 2021
Normally, I don't comment on things online, but I was compelled to share my knowledge because I know how frustrating it is to have those drain flies, gnats, or whatever they are in your home. After 3 yrs of trying everything including pest control and bleach and ammonia, I finally went to a small Ace Hardware store and purchased Sani Sticks and Terro Fruit Fly Trap. And they together did the trick! Amazing! Hallelujah! Not sure if one works without the other, but who cares, I got rid of them!
Martha Stewart Member
May 4, 2021
Was not helpful at all. I read it twice thinking I missed something. Useless, it said nothing
Martha Stewart Member
March 30, 2021
This article is completely useless and helped me in no way at all.
Martha Stewart Member
March 30, 2021
This article is completely useless and helped me in no way at all.
Martha Stewart Member
March 25, 2021
I’m afraid this was not helpful at all.
Martha Stewart Member
March 25, 2021
I’m afraid this was not helpful at all.
Martha Stewart Member
March 22, 2021
There was nothing written here that tells me how to get rid of any? It just gave a description of the two types? Weird. Not helpful at all. Sorry
Martha Stewart Member
March 22, 2021
That wasn’t worth the read, honestly. There is no way to rid your home of either for good!
Martha Stewart Member
March 22, 2021
I have read this brief article three times, but I seem to have missed the section that tells specifically how to get rid of either fly. “Hire a plumber or exterminator” is not the level of advice I expect from Martha Stewart: Martha can do better than that. This article is embarrassingly useless.
Martha Stewart Member
March 22, 2021
I had hoped for some helpful info. This is really a garbage article, sent under Martha Stewarts magazine/on-line presence. Social media at its worst L Small in Boynton Beach, Florida
Martha Stewart Member
March 22, 2021
The advice I was given by an exterminator was to exterminate drain flies by pouring bleach down the drain periodically. Definitely worked.
Martha Stewart Member
March 22, 2021
This article told us nothing. Here is a helpful hint.....apple cider vinegar and a drop of dish soap. Leave it in a glass overnight near the issue. The next morning most of them are gone....into the glass.
Martha Stewart Member
March 22, 2021
This article told us nothing. Here is a helpful hint.....apple cider vinegar and a drop of dish soap. Leave it in a glass overnight near the issue. The next morning most of them are gone....into the glass.
Martha Stewart Member
March 22, 2021
Soy to say, but this is one of the least helpful articles ever. I expected to read a more detailed description and actual treatment methods of getting rid of the fruit flies, what was said was common sense.