Pyrethrine is also very good stuff. Works against lots of pest and is a chrysanthemum extract.
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Agree, but the problem with fungus gnats is that you’ve got to kill the larvae that are inside the pots … 
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you could also get some pantyhose and wrap the entire pot in them, up to the stem. The flying ones won’t be able to lay eggs, and the larvae will just die off. Would work well in conjunction with some of the other methods.
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Ok I have to ask, has anyone tried the steel wool method? I have never had gnats but have read several times that if you cover your medium with steel wool than the hatching bugs can’t get out and the adults cannot get to the medium to lay eggs. This ends the cycle once all in the soil have hatched. It is a simple and effective way in theory but I am curious if anyone has tried it?
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Never seen steel wool, but I’ve seen people use sand, rice hulls, or Diatomaceous earth, all very similar. Just gotta cutoff their food.
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The problem with sand and DE is that you’ve got to water from the bottom, I also heard gnats get inside the pots through the holes in the bottom, so guess only a combination of various methods will finally beat them …
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Thanks. I am just amazed it has not been explored more. There are countless references to it when you Google it. I would think folks would jump at such a simple fix. Oh well, the method is out there for anyone who want to try. Here is hoping I never have to try it myself.
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No, but very fine sand. Covered the soil with it.
Worked a charm, but I can’t do it every time as I reuse my medium.
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Steel wool will eventually oxidize and rust. You’ll end up watering that into your medium. 
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Yes but it is made of non toxic metal, worst case is you add some iron to your medium which is not a bad thing.
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There is stainless steel wool as well.
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Yep but by the time you pay for the stainless steel wool you could have bought 3 new bags of soil 
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add insect frass to you soil mix.
work very good …
Get this and sprinkle and scratch into the top 2” of the soil. They’ll all be gone in a week- 10 days and will not return if you apply to all your pots. Haven’t seen one in months.
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Suggested to me by Lady Zandra who swears by it, I’ll be using a food grade product she uses during veg that kills them dead and is safe.
and am hoping for the best results…
Last bag of soil I bought at a Ranch style feed store, so many eggs were already laid in this stuff, when hatched it looked like I had used live ants as a medium… so, trying something new, I kill 2 flowering plants with Hydrogen Peroxide over use and gave them powdery mildew…
don’t be stupid, learn from me instead… hehe
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I have used the hypoaspis miles/ scimitus without success. Perhaps because the accari box was not in good state. It was for 5m2 and I used it in 1m2 and very few accari could be seen live (with magnifier/microscope)
Now I buyed some BTI and I’m going to test it this week. I will report if this works.
I also have cut come TNT (non woven fabric) to put over the pots… hope all this erradicate the gnats.
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