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Got Fungus Gnats?

Discussion in 'Indoor Marijuana Growing' started by Giggity Goo, Jul 6, 2009.

  1. Cover your soil with a 1/2" of perlite and put a Hot Shots No Pest strip nearby and they'll go away fast. I was literally infested with these buggers, now they're gone (or at least suffocating under the perlite). :hello:

    Sorry for the crappy blackberry pic:
  2. Thats cool I didn't know perlite would work for that. Diatomaceous earth also works great for most pests actually. Thats what I used when I had a gnat problem with my houseplants.
  3. Me neither but I read it in this PDF:
    Google Viewer

    Diatomaceous earth is probably better but I don't know where to buy that. Any ideas?
  4. Most nursery's should carry it, thats where I get mine anyways. You could always try hd or lowes though.
  5. I've got fungus gnats bad and am 6 weeks into flowering. i read that neem oil can be used effectivly as a soil drench. anyone have any experience with this or directins on how to do this?

    wondering if i can just spray the soil and underside of canopy to get rid of these.

    will see if i can find any of that Diatomaceous earth localy as well.
  6. Dude gnats during flowering is really bad lol. Your buds will act like sticky fly traps and they will actually get stuck on the buds. I would get a strong breeze on your plants 24/7 till your gnats go away. Neem oil works alright but you'll need something to cover your soil with to stop the eggs from hatching and reaching the top of the soil. I would be careful with spraying neem oil on your plants in flowering as this could encourage mold, just do it very very sparyling. Neem oil helped with my gnat problem but didn't take care of it all by its self.
  7. well, they just broke out an i have not seen a single one stuck to a bud yet and I am presently checking for readiness on some plants iwth a microsope.

    what about dish soap in the water combined with the diatomaceous earth and some yellow fly strips?

    hope i can get this under control quickly.
  8. Diatomaceous earth only works if you cover your soil with it, not mix it with water and soap. While dish soap and water do work good I found that baslmic vinegar worked better, not diluted just poured straight into little glasses then placed around the base of my plants.

    Well since your problem has only started not many would be around to get stuck on the buds, but if the problem gets worse you can count on noticing gnats stuck to your buds. Im guessing your plants are pretty resinated at 6 weeks, thats what makes them stick to the buds. Go touch your buds and your fingers will have sticky icky on them lol now imange what that does to little pests.
  9. yes, definitly some sticky buds going on.

    i read about vinegar (apple cider, actually) and what i read is that it was just an attractant for the adults. it would have to be used in conjunction with the sticky tape to actually trap them. also the larvae (or whatever they are) beneath the surface of the coco need to be suffocated as well, right?

    so are you saying that the DE cannot be used to cover the top of the coco compltly if i am also using drip stakes for irrigation? i had no plans to mix dish soap directly with the DE and then apply it to the plants if that is what you are implying. i was suggesting that both techniques might be used but not necesarily at the same time.
  10. well Im having the same damn problem. my post

    But what technique should I use. The perlite and Diatomaceous earth sound like a great idea but what should I go with? Im probably running out of time and need to act quick. Any follow up on your perlite experience Giggity Goo? (lmao quagmire)

    Diatomaceous earth sounds pretty promising also. What should I go pick up after work tommarow to do the job?

    This seemed helpful also, anybody have experience with the potato slices?
  11. Idk how well potatoe slices will work, always worth trying something new though. With perlite or Diatomaceous earth you just need to put about 1/2 an inch over your soil. The Diatomaceous earth will actually cut up the pests as they burrow through it. This way you keep the adults from laying more eggs and make sure the larve never reach the surface.

    The thing with vinegar is it does attatract the adults. Once they dive in they'll never come back out. Just get a few small cups or bowls and fill them with a little bit of vinegar and place them around your plants. I've never tried apple cider vinegar as the only thing I had was balsmic and the dish soap. And like I said before I think the balsmic worked way better then the dish soap. You don't need the sticky traps for it to work I would still get some though, its always good to be on the safe side when you have a bug problem.

    Sorry resinlip I just misinturtped what you said is all lol, it happens on stoner forums though hahaha.:D You want about 1/2 an inch of DE over your medium.

    P.S. Pests and mold find it hard to live in an environment thats constantly bombarded by air currents. Use that info however you want. :smoking:
  12. If you are using traditional nursery pots with the holes on the bottom-sides, they usually lay eggs in those holes. Spray a little neem into those holes. I've foung that works too.
  13. i do have air circulation fans and the plants are in 8" cocotek liners filled with coco.

    i also do have fans in the grow room.

    the number of gnats seems to have subsided significantly since i first posted and all i did so far was to move teh 4 plants around on the grow tray to get more air flow under the canopy and cleaned even more junk that was not seen before laying in the grow tray. now there is just a small group of the gnats hanging around the drain. i also did a ton of ladybugs so perhaps they were hungry after being stored int eh fridge for who knows how long. i don't think it is one of their regular foods.

    just laid out balsamic vinegar and fly strips so i expect that to start working for the adults.

    will try the potatoe slices as well (apparently this draws the larvae into the potatoes and you jut throw them away after a few days.

    as for the eggs beneath the surface, i am still not sure what the best choice is here. can dish soap do the trick? that would be the easiese thing to do imho. after tha, a layer of something over the top of the coco, preferably DE.
  14. So I put a layer down of perlite in each pot. Hopefully this shit really works
  15. This thread makes me scared. + rep for the tips
  16. Gnatrol Fungus Gnat Control

    Gnatrol is a highly selective, biological larvicide for use in greenhouses to control fungus gnat larvae. It may be used on a wide variety of ornamentals, as well as all bulb crops, bedding plants and vegetable sets. The active ingredient is Bacillus thuringiensis israelensis (Bti). Once the larvae have ingested the insecticide, protein subunits paralyze the fungus gnat larvae, which stop feeding immediately and die - usually within 24 hours. Will not harm people, pets or the environment. Mix 1-2 tsp. / gallon of water. For heavy infestations use 4-8 tsp. / gallon of water.

    As part of an Integrated Pest Management (IPM) program place Yellow Sticky Traps horizontally to control adult fungus gnats.
  17. DEFINITELY! I sprayed neem oil and taped up the holes for now.
  18. I would just like to know what are the signs you have fungus gnats? Because I think I may have them but i'm not sure. When I was watering I saw some tiny black bugs with wings moving around the top soil. I tried to get one under a microscope but I always crush them to oblivion on accident because they're so small.
  19. You dont need a microscope to see em. About the size of a fruit fly. You can easily squish 'em with your fingers. They do walk really fast on soil so you could have em. Stir the soil up a bit and see if a bunch come out.
  20. put ladybugs in your grow. they are canivores. just spray a little water on the plants for drinking.

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