I would love to hear what fellow houseplant havers do to get rid of gnats in the soil. I feel like I have tried everything… drying out the plant, hydrogen peroxide mixture, sticky pads, one of those plug ins that attract the bug, repotting, lower humidity in the room… like my goodness! I don’t feel like they would get on my nerves so bad if they were always in my face, in my food, in every room… it’s not a lot but I definitely see a couple a day. Both of my plants are easy to take care of, so they don’t require a lot of watering so I wait until soil is completely dry before watering again. They both have drain holes in the bottom of their pots with a gap to let it drain if needed. They sit next to the window where they really love it. I would like to know what others to to get the gnats to stop!
by thatgirlmakchats
19 Comments
I feel like diatomaceous earth did a good job fixing my gnat problem. Only works when dry tho so don’t water your plant when you apply it
I used those traps and sprayed a diluted mix of hydrogen peroxide on the top layer of soil every week and it eventually took care of them. Surely someone else will have other methods.
Don’t over water. Let the soil dry out between watering as much as possible.
Have you heard the good word about beneficial nematodes
I bought a bunch of those small squishy toys from the dollar store and apparently gnats can’t resist landing on them because they all became covered in tiny little corpses very quickly. They can be washed with soap and reused a couple time too
Mosquito bits. I sprinkle generously on the top soil and water as needed. It kills the eggs and larva, I believe, sob there is a little delay but it has worked 100% for me. No question.
You can also try about 1.5 inch layer of stand. The prevents larva from reaching the surface and adults laying eggs. This has worked for me but made watering a little harder to gauge.
Of those two options, mosquito bits would be my choice.
Beneficial nematodes. No stress for your plants and legit works. I tried everything to get rid of them and this finally stopped it.
Check your sink/garbage disposal pipes. That’s where mine were coming from.
As someone who’s had 33 plants and a gnat problem. Up-pot to a size about two inches bigger from the top and fill those two top inches with sand. Little suckers can’t dig in and if there’s any under the sand they can’t dig out thus killing them. Only downside? Your pots get HEAVY. I’ve never had to buy neem oil, DTE, or mosquito dunks since. There’s no better feeling than knowing you’ve won the battle because you start seeing less and less until they’re gone. Happy to say I’m going on month 9 now since December when I first started and not a pest in sight. I kinda miss them. (JOKING)
I sprinkle a little cinnamon on top of the soil — no gnats.
I read somewhere that it worked. I was skeptical, but I tried it any way. It works great for me!
There are no hacks. There are only 3 things that actually work:
1. BTI-based larvicide, aka Mosquito Dunks/Bits or Gnatrol. This really does work, but you need to carefully read the instructions and follow them to the letter. Don’t fertilize, copper kills the BTI (a bacteria that infects the larvae).
2. Nematodes. Similar caveat about getting the right kind and following the instructions carefully.
3. Drying out the soil completely for 30+ days. Except for succulents, this kills the plant. So it’s mostly a no go (but hey it kills the gnats!).
You also need to understand their lifecycle. You can really only wipe them out in their larval stage, so you will see them for around a month while treating, then they’ll all die. Treat all your plants, not just affected ones. It takes persistence. One adult can lay 200 eggs, so while the sticky traps help, it only takes a few to keep the colony going.
Things like sand, DE, or hydrogen peroxide might work on a small number of gnats. But once they really get going, they’ll breed in the bottom of the pot, your sink drains, or anywhere else with moisture, and those treatments won’t work.
Water less and mix mosquito bits in the soil
Find your friendly house jumping spider and relocate it to your plants
Carnivorous plants
Soda water
Fire
Nematodes
Or
Stratiolaelops scimitus
A mix of a few methods. Like Peroxide, then Dunks, finally top with Dio Earth.
Get some nematodes. Never looked back since I tried it.