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Discussion in 'Growing Marijuana Indoors' started by tikandsync88, Dec 31, 2012.

  1. Will using SM-90 get rid of gnats or hurt my plants in any way?
  2. I had this problem before. cover the top of your soil with a layer of sand and a couple of fly traps will get rid of them. Keep the soil covered with sand and they shouldn't return.
  3. Get some mosquito dunks. Soak them in a bucket of water, and use it when you water/fertilize. They'll be gone pretty quick. Works every time. :)
  4. Try an inch of clean/washed sand and a sticky fly strip and the gnats will dissappear.The SN90 will work as a soil drench but sand is cheapest.
  5. I had that prob and I put about 2 inches of sand on top with about a inch of pea gravel on top of the sand. This worked for the most part but they started going in through the drain holes in my pot. So u might want to put sand on the bottom of pot
  6. #7 pointswest, Jan 2, 2013
    Last edited by a moderator: Jan 2, 2013
    SM-90 is not a pesticide, it is a wetting agent for spray applications. It has no pesticide ingredients, it is similar to liquid soap.

    Get some Gnatrol and water 2-3 times with it. This is the same chemical that is in the mosquito dunks (Bti). Do not use the Merit on your plants unless you like smoking pesticides.

    Fungus gnats are a result of too frequent watering, let the top of the soil dry between watering and you will not get gnats. Everyone blames the soil products, but it is usually the grower's watering practices causing the problem.

  7. I did the sand thing with no joy, it did reduce them but it didnt get rid, i have tried everything.

    Im fighting a losing battle or thats how it feels.
  8. Is there any standing water near your grow?....might be an outside source problem.
  9. Thats exactly what it is, a fucking park, its full of them.
  10. If you had the little water catch trays under your plants..put sand there too so they dont enter the drain holes.The gnats are just annoying the larvae eats the roots so just block the holes or get buckets with bottom facing holes....kinda fucked with that park your right.
  11. I use wilma systems so i dont have trays, thats why i cant let the pots dry out cos i feed 4 times a day. Im moving home soon so i will just battle on with stick traps until then. Thanks for the advice though bro.
  12. #13 Buffalo11024, Jan 2, 2013
    Last edited by a moderator: Jan 2, 2013
    Beneficial bugs, research them, you may find some suitable to handle the problem outside your pots.
  13. Thanks my friend, i tried lady bugs. The first time they died cos they hit the light :eek: the second time i sprayed them with sugar water so their wings would stick, they couldn't deal with the proplem. They just populate too quick.
  14. How many you put in?
  15. I used 20, both times. Its the park, i cant win really.
  16. R they doing any harm to ur plants or just r annoying
  17. To be honest i get good results so its more annoying, im sure they effect my plants in some way.
  18. Thanks I was just wondering in case I ever get them
  19. I read somewhere about dishsoap but don't know for sure

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