I got back from a weekend away to my apartment full of fungus gnats from my giant taro and a couple of pothos plants. I have been scouring the internet for answers and limited it down to a few products. I water my plants once a week and limited it once I saw a few bugs and have them all in a south facing window with pretty good light. I already have traps on the way and until then I’m using the ACV and dish soap trick, but I’m trying to decide if mosquito bits or diatomaceous earth is the way to go. Which one would you recommend? The mosquito bits say not to use them on indoor plants but it says otherwise online. Help please!
by Ihatefrogs_
33 Comments
Nematodes
If you soak the bits in water and water your plants it will kill the bugs and their eggs. I have done this numerous times.
Diatomaceous Earth is great too but you need to be careful with it. Do not get it in your eyes or inhale it.
Bacillus thuringiensis israelensis and sticky traps.
BTI is the bacteria strain that’s used in mosquito bits. Mosquito bits are only 3% BTI though. Check out organicbti website for gnatrol wdg in small quantities. It’s 30+% and water soluble.
Use the gnatrol to get control, then switch to the bits about a month later to maintain the BTI population.
I use systemic granules. Also don’t water weekly. Only water when the top two inches of the soil is dry. You can just stick your finger in.
The one that says for fungus gnats…
Jokes aside BTI is THE most effective. I’ve never had problems with using it indoors. I don’t have pets so maybe double check pet safety but otherwise I’d go with mosquito bits.
they are from bagged soil, a yellow sticky trap with flying insect pheramone will get them all ventually
I hate fungus gnats. I’ve tried all the stuff. Some works and some not so much. The best thing that works for me, I repot and resoil. I use sticky traps to find out which plants have it the worst and only repot them. Works everything. I kick myself every year for wasting time and money on anything else.
I’ve also been told by owner of a nursery that a layer of sand will prevent them from laying eggs in the soil/or the large from being able to surface. Haven’t tried it yet.🙄
I’m using fine BTI powder in a liter of water at a time and idk it doesn’t seem like it’s doing much. Been a few weeks now. I’m using every 7-10 days. Some of my plants don’t need that much water so i just do enough to keep the top wet. I got nematodes this past weekend and poured them in after reapplying the Bti. Hope it works otherwise I’m seriously gonna start yeeting stuff. I got the best results from DE but they came right back when we got new plants. And DE was so messy and there’s not enough space to sprinkle onto the soil. Need wider pots. These fuckers literally fly into my nose while I fucking sleep, they swarm me when i have the curtains open while it’s sunny and they swarm me when I style my hair. I can’t get the fuck away from them, I can’t relax in bed, I can’t relax on the couch (where i am now and one just flew into my god damn face) and they are driving me literally insane. Apparently they can cause pink eye? Also i have cats and they like to burrow in the litterbox too. Can’t put anything in there to help with that just have to scoop regularly .-. i hope you have better luck ridding them than I do. I think our soil is the culprit but idk how to rid of them in the bags of soil. I saw someone say boiling water but that might melt the bag. I could put the bti in but it was expensive and hard to find in europe.
Ive successfully used the mosquito bits. I applied 3 applications 4 days apart. Fungus gnat life cycle is 4 days hence applications every 4 days. For maintenance apply every month.
You said you water weekly, so that might be a problem there. No plants should ever be on a schedule. Just doesn’t work like that for indoors. Stick your finger in the soil and only water when the tip of your finger is dry. Your soil is probably staying damp for too long. I know you said you extended the time in between waterings but again shouldn’t have them on a schedule!! Nematodes are also really cool for fungus gnat larvae! That’s what I use
Ground cinnamon at base of plants. Gets watered in and kills the fungus the larvae eat
I eradicated a really bad infestation with just mosquito bits. Dissolved in my watering can and use them on my plants for a while. Did not take long. Yellow stickies to catch the flies, mosquito bits water to kill eggs.
Mosquito bits did the trick for me after months of failed Systemic Granules use.
Neem oil i supose
1 cup h2o2 (3%) to 4 cups of h2o drench the soil and then put diatomaceous earth on the top and hang some sticky traps
Mosquito bits and sticky traps!!!
Diatomaceous earth DOES NOT WORK ONCE WET. You have to water. Once you do, it’s moot. If you apply it to wet soil, it’s moot. DE doesn’t work unless you keep it completely dry.
I only got rid of mine by repotting everything
Got rid of them in 3 days by spraying the soil with a mixture of rubbing alcohol, dish soap, and water. I also did a single very quick dunk of the bottom 2 inches of the pots in dish soap water ( I think it was about a tablespoon in a gallon)
Leave the mosquito bits soaking in the watering can and use the water consistently. It will take a while for the adults to die off but it will work.
This has been said before already but nematodes combined with sticky traps worked for me. Also make sure to get rid of any bags of soil etc you may have laying around; you need to treat all soil in the house or they WILL find and infect it.
The infestation that I had was absolutely catastrophic, but after just a week the gnats were gone. Haven’t seen one in almost a month now.
I wanted to use Nematodes as a last resort and I found that using the following steps helps me greatly reduce the gnats. I have not killed them all yet, as I started this only a month or so ago, but the way things are going, I am confident that they will be gone soon. Hope this helps.
– Skip a week of watering if possible. If not possible, use only the necessary amount of water for only plants that require it. This may need to occur more than once in non-consecutive weeks
– Buy stainless steel loose tea infuser balls and fill with the mosquito bits. Allow this to infuse into the water you use to water the plants. I change the bits out every two weeks. This will need to occur for at least a few weeks, if not more, until the gnats are fully eradicated. As I mentioned above, I have been doing this for about a month and have greatly reduced the number of gnats. It probably won’t hurt to continue this indefinitely to prevent future infestations.
– Use yellow sticky traps. These will not only help you catch the adult gnats, but will help you gage when they are fully gone.
Put sand on top layer of soil and add diatomaceous on top of that. Additionally, put up the sticky bug traps on windows and around pots. Make sure you don’t have any old potatoes or onions hiding somewhere in the kitchen. Flush sinks and drains with hot soapy water. Repeat the above until they are gone.
Gnatrol.
Works well. I use little cloth bags that I can put the bits in and put it in my watering can. This way they don’t clog anything or mold on the soil itself. Can just remove the bag and put in a new one after a few cans worth of water. Let the fresh bits soak in the water for a day before watering.
I also use the sticky traps. Works well as a combo.
>The mosquito bits say not to use them on indoor plants but it says otherwise online.
I’m guessing this is because the manufacturer never went through the EPA licensing for using these on indoor plants, so they are absolving themselves from any sort of liability.
I used to work with one of the old-school researchers who was with the company that developed the biotechnology where the “important” bit of BTI was incorporated into transgenic plants, way back in the day. It’s very safe from a mammalian standpoint. But this application doesn’t have licensing by the feds as such, that’s all.
That DE and getting rid of bags of soil in my house solved a nasty infestation for me.
1 part hydrogen peroxide 4 parts water. Only thing I use. And the roots like the bubbles.
Summer = every watering. Winter = once every three waterings.
Mosquito bits, sticky traps, and a nice thick layer of sand on top of the soil
You already have heard it, but I’ll throw another hat in the beneficial nematode ring. I tried BTI tea for months and they just kept coming back. One treatment of nematodes basically knocked them all out. I kind of couldn’t believe how well it worked. In recent weeks some have come back because I’ve been overwatering again, but I’m not stressing it now that I know I have nematodes on my side.
Gnatrol
I eliminated my gnats with both DE and Mosquito Bits. The MB will work on its own but takes 3 weeks. I covered all of the soil with 1/2” of DE leaving a hole in the middle of the plant where I could water with MB. As the gnats dug through the DE they would die. It was an immediate way of getting rid of the infestation. Eventually the MB did its thing and I removed the DE.
Beneficial nematodes, works like a charm. Just google
Try drying the soil + sticky traps.
Extreme case ive heard baking the soil in the oven can help.