Controlling Houseplant Fruit Flies & Fungus Gnats Naturally

November 05, 2008

As a garden consultant, I hear this question a lot: What do I spray to get rid of the fruit flies in my house plants?

The first thing I try to determine is whether the pest is truly a fruit fly or is actually a fungus gnat. They’re both tiny and truly annoying. Fruit flies tend to invade our kitchens, particularly during harvest season and sometimes they move into our houseplant soil along the way. I’ve posted ways to use carniverous plants in your kitchen to control them, and some of my readers have shared their methods as well in this post.

Sticky Stakes for Houseplants
If the problem does turn out to be an infestation of fungus gnats, the more likely culprit to live in houseplants, I steer people away from the pesticide aisle and suggest a few simple environmental and pesticide-free control options:

  • Add a thin layer of pebbles or gravel to the top of the potting soil in your indoor plant containers. Fungus gnats lay eggs in the top layer of the soil and hatch from there. They can’t do this in pebbles.
  • Clean your catch trays. Gunky catch trays can be egg-laying spots for fungus gnats.
  • Insert sticky traps into your houseplants. These are inexpensive, pesticide free papers covered with a sticky material. As the gnats buzz above your plant, they are attracted to the yellow color and smack to the sticky surface never to fly again.

If you’re not sure whether you’re dealing with fungus gnats or fruit flies, know this: Sticky traps attract both pests and may solve the problem regardless!


  1. Jack says:

    Really good suggestions for controlling fruit flies and fungus gnats. No one really want to use chemicals anymore as a solution.

  2. Ash says:

    Getting rid of fruit flies can seem like a daunting task for many people, but its easier than you think. We don’t want to have toxic solutions, however there are many products marketplace which offer a natural and non-toxic solution to combat fruit flies to prevent health issues.

  3. Rick Coash says:

    I am in an apartment and have an indoor composting bin with “red wiggler” worms. I need to know if there is an herb that I can but in my bin that will combat my infestation of fruit flies, that will not be toxic to the worms.


    Rick Coash (co-ash)

  4. rhaglund says:


    Unfortunately I don’t have the perfect remedy for your fungus gnat infestation. You could trya tip another reader sent in: put a shallow dish filled with vinegar on the top layer of the worm bin (make sure it won’t spill). The flyin’ buggers may be attracted to it where they will drown. It won’t kill them all at once, but it may eventually break the life cycle. If my indoor bin ends up with a hatch, I set the bin outside where it is cold for a bit to freeze off the gnats. I may lose some worm productivity this way, and I have to take care not to freeze the entire bin, but it can help beat back the gnats, which like the warm. Not sure if you can do this in an apartment, but it’s an option.

    And, worst case, clear out the entire bin, sorting out your worms to keep. Spread the compost or recycle it outside the house. Clean your bin well and start over taking care to keep everything sealed and free of already-infested gnat goodies.

    Thanks for writing in & good luck!

  5. Flower Pot says:

    These are some really good ideas I haven’t run across before now…thanks.

  6. […] Is it a Fruit Fly or is it a Fungus Gnat? var a2a_config = a2a_config || {}; a2a_config.linkname="Great DIY Fruit Fly Control"; a2a_config.linkurl=""; […]

  7. patty says:

    Would these gnats make the leaves on my plant curl or have what looks like tiny white dots in the veins of the leaves ?

  8. Patty,

    Fungus gnats can do damage, but I’m not familiar with them creating tiny what dots on leaf veins. Curling leaves and dotting sounds suspiciously like there was an insect with sucking mouth parts involved. Aphids, for instance, will suck the juices out of young leaves, leaving them damaged and curled as they mature. But, by the time the leaves are unfurled and curly, the aphids may be long gone. Insects like mites will suck the juices out of leaves leaving them looking speckled with white. So, not sure what’s causing your issue, but maybe this will help you dig a bit deeper. Thanks for writing in & good luck!

  9. Sarah says:

    I have had a problem with what I think is fruit fly. For 5 years they have invaded my house plants and in several cases caused them to die..
    The fly is living in the compost and the lavae is white an and if disturbed jumps about. I have tried jeyes fluid which seems to work on the adults and lavae but I cannot seem to get rid of them all.
    I am fed up with my plants dying, is there a remedy at all for this problem?

  10. In addition to what’s in this post, you could try putting gravel on the tops of the soil of your houseplants and allow that to remain somewhat dry. They can’t live in this environment. Sticky traps help break the cycle too.

  11. Christine says:

    Some very good suggestions. I am using the fly paper traps right now, one in my front room and the other in plant/sewing room. I also use apple cider vinegar in a medium size jar cover with plastic wrap make a few holes and set near plants, this actually works well. I am also going to try small decorative pebbles on the surface of my house plants..

  12. Shadow says:

    The sticky traps hardly caught any at all. They didnt bother.

  13. Try placing them closer to the swarms and you might have better luck Shadow.

  14. Linda says:

    I do a lot of canning and freezing of fruits in summer and fall and have lots of fruit flies. I solve the problem by placing a small dish or glass on the counter half full of apple cider vinegar with a couple drops of dishwashing liquid in it. The fruit flies get in that solution and drown. Has worked for me for years.

  15. Glad you have a solution for those suckers Linda!

  16. Josie says:

    Can you use any other vinegar other than apple cider? White vinegar? Basalmic? Red wine? Thanks.

  17. Josie, no reason you couldn’t try the other vinegars.

  18. Kristine says:

    Hi! It has now been weeks since my fruitfly problem started and I’m going crazy! I have 30 something plants in my livingroom, big ones that i’ve had for a decade and smaller ones and they have started to dwindle and die, and that’s especially sad when I’ve had them for years and have somewhat of an emotional bond to them, however strange that may sound.. Anyways, I have tried EVERYTHING! Tons of deathtraps and bombs to kill the flies, added pebbles and stones to my plants, put down matchsticks into the soil (my mother said this could help) and it’s still out of controll and I can’t get rid of the horrible mini monsters! Help! What more can I do??

  19. Kristine,

    This may sound like a lot of work, but sometimes a complete soil exchange can help. That means removing all the soil, rinsing the roots, washing and sterilizing the containers, and replanting with fresh pebbles and traps on top just in case. It could be that they’ve infested other areas, or it could be that you have something else going on as well, so its hard to know for certain. But, you could try this. Bon chance!

  20. Anthony says:

    I read somewhere a while back that cinnamon on the top soil works. It’s an antifungal and keeps top layer dry. Put some in a small salt shaker and its easier to get all around the plants. I out a thick layer after watering and it last about a month. If you do this forbade couple months they should be gone. I slacked off a little and the flys came back, but only about 10 or so. Not 50-100 or more like I had before.

  21. Kristine says:

    Dear Garden Mentors, thank you for your reply and help.. it has now been a week since I changed all the soil and even chose to throw away the worst infested plants and tried to freeze some of the biggest hardiest plants outside for some minutes in 4 minus celcius degrees… last thing I tried was spraying all my plants and new soil with hairspray and fire – can you see it?? I must have looked like a maniac.. But sorry to say they are still here and still killing my plants! Is there some poison as a last resort I should try? I have cats and a parrot (who btw eats fruit and fruit pellets – where I suspect the fruitflies all comes from) so it can’t be harmful for longterm after the spraying for the pets in the house.

    I am willing to try almost anything short of getting rid of my plants!

  22. Kristine,

    Try taking a sample to a local extension office or nursery to get help identifying the problem so you can use the right technique or product. Good luck.

  23. pam says:

    I have the same problem with fruit flies or fungus gnat in my indoor plants as well in my greenhouse. what I did was putting the houseplant sticky stakes and it does work but I was wondering why it doesn’t seem to go away. I kept replacing the sticky houseplant stakes. I checked the back leaves and I found eggs and also thought of coming from the soil. What I did was I sprayed with homemade insecticidal soap. I mix apple cider vinegar. castille pure soap, garlic, olive oil and it works for me. I had to do manual to wipe off the eggs from the leaves so the leaves would look nice and they loving it. (Jasmin plant)

  24. Sara says:

    Could I suggest mixing some citronella oil with some water in a spray bottle and lightly misting the plants ? I sell Young Living Essential Oms and I know Citronella is a bug repellant … Just might work …I just don’t know if it would harm the plants….

  25. Sara have you tried your suggested technique or just telling people that citronella is a bug repellant and leaving it to them to hazard spraying it on plants?

  26. R. M. says:

    If you are having problems with fungus gnats/flies, try mosquito dunks. You can get them at most home improvement stores. I wet them a bit and break them apart then apply some to the top of the soil and water the plants. The dunks are supposedly organic and work wonders. In two weeks you should be fungus gnat free. It kills the larvae. No larvae no flies/gnats. Keep the sticky traps out to catch the remaining adults while the dunks work their magic. Hope this helps with those having issues, it sure helped my indoor garden. No more pesky flies/gnats buzzing around bothering me.

  27. As we state in our FAQ, we understand that we may agree to disagree with each other. We’re approving R.M.’s comment, but we don’t necessarily approve this technique. First: “Organic” doesn’t necessarily mean safe in all situations. And, if a dunk is created for one issue it doesn’t mean it should be used for another. Consider with caution.

  28. Jeanette says:

    Cinnamon is the best thing i’ve read so far. Also theirs a bacteria that works and a flower it starts with a c but basically a type of daisy!!

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