How Do You Get Rid Of Gnats?

dr2brains

Well-Known Member
I have a cabinet grow w/ two chambers.
I started the first grow about four weeks ago....No Problems! (for the most part)
seedlings 11-14-11 007.jpg

I started the second grow 8 days ago....
seedlings 11-15-11 003.jpg

And now I seen 3 or 4 small gnats flying around!
When I check the two chambers, the gnats are only with the small plants.
(there's a hole that I keep open between the two chambers during 24/7, but the gnats stay in the one chamber.
How do I get rid of them?:?:
Will they harm them?:?:
 

2layz2p

Well-Known Member
No pest strips will get rid of them in one/two days.

Why ur lady's frowning, low on water or sleepy time?
 

bamfrivet

Well-Known Member
add a layer of sand to the top of your soil and they wont be able to lay their eggs in the soil. the adult gnats aren't anything to worry about, it's the larva that do the real dmg. they can eat your roots and starve your plant.
 

boxorain

Member
Tried that last year; slows them down but doesn't stop em. Try Gnatrol.

add a layer of sand to the top of your soil and they wont be able to lay their eggs in the soil. the adult gnats aren't anything to worry about, it's the larva that do the real dmg. they can eat your roots and starve your plant.
 

TWS

Well-Known Member
Man, I swear gnats are harder to get rid of then mites. My no pest strips did not get rid of them. Spraying insectide on the top soil only knocked em down a bit. The only thing that seems to be working for me is a soil drench with azamax and covering the tops of the pots with perlite.
 

D.O.G

Member
i have a bottle of azamax, but a little nervous about using it. i would like to hear more peoples dosages on it.
 

jpill

Well-Known Member
cinnamon. works like a charm. ! sprinkle it on the top soil. I Also have some bug strips just in case. Im currently fighting those bastards right now , Thanks to Roots organics potting soil. Those fuckers have bugs in their soil for reals. Try cinnamon dude it works i promise! it sounds weird but those fuckers will peace out asap!
 

dr2brains

Well-Known Member
I'm gonna try it. I'll let you know how it turns out.

cinnamon. works like a charm. ! sprinkle it on the top soil. I Also have some bug strips just in case. Im currently fighting those bastards right now , Thanks to Roots organics potting soil. Those fuckers have bugs in their soil for reals. Try cinnamon dude it works i promise! it sounds weird but those fuckers will peace out asap!
 

blakasassin1

Active Member
hey man i bought some ecosense insect soap and am spraying it but before that i use to chop of raw onions and put them on the rims of the pot i heard the bad smell keeps pests away i will try that cinnamon
 

Stickystickyganja

Well-Known Member
Im using granulated neem to control mine. I mix a tablespoon in before i pot anyplant. Months later they will arrive again, all I do is sprinkle some on the top soil and water normally.
 

elduece

Active Member
If things get bad, a layer of DE (diatomaceous earth) will break their reproductive cycle by killing egg laying adults as they emerge from topsoil or land in it.

While aerating water, routinely put a mosquito dunk in a paint strainer and just let it steep until the water is done. The water for all my plants receives Bt at every watering through this.

Save the cinnamon, azamax etc. Also, cinnamon is anti-fungal and might work against your plant roots instead.
 
  • Like
Reactions: TWS

dr2brains

Well-Known Member
cinnamon. works like a charm. ! sprinkle it on the top soil. I Also have some bug strips just in case. Im currently fighting those bastards right now , Thanks to Roots organics potting soil. Those fuckers have bugs in their soil for reals. Try cinnamon dude it works i promise! it sounds weird but those fuckers will peace out asap!
Sprinkled cinnamon yesterday....didn't see any gnats this morning!
Keeping my fingers crossed!
 

Beansly

RIU Bulldog
Persistence man.
You have to affect their ability to reproduce. Also, any other part of you house has fungus gnats flying around like your sink, your garbage cans or you clothes piles, then you need to get rid of those too.
Keep the grow room clean of dead leaves and any standing water puddles, big or tiny. Keep a thick layer of soil above the root ball. At least 2 1/2 inches. If you can easily swipe away the soil on top of the pot, and see the roots, then you'll have more bugs. cause they feed on those top roots. Sand is a band-aid and it really messy onces it comes time to water. Plus, imo, it affect the gas exchange between the soil and the atmosphere, but Idk for sure. It just seems like the sand lets less air pass through than than normal when watering but that's just my opinion. If you mix your own soil, add Diatomacious Earth to it as it controls bug and larva in the soil.
Try getting yourself a herbicide. I use Ed Rosenthal's Zero Tolerance. It's made with essential oils of cloves, cinnamon, rosemary and some other stuff. This stuff kills gnats on contact. It's awesome. Use it to spray the top of the soil in the pots or wherever they're congregating to kill them in mass quantity. The ones that fly are the only one that reproduce, so one you reduce their number, controlling the population is a lot easier. Kill the flying ones first...
I also use potato slices. If you put raw slices of potatoes on the topsoil, the gnats lay their eggs there, and you just throw them out at the end of each day.
You do enough of that stuff, and I'm sure you'll see less and less gnats. Oh, yellow sticky traps also help, but they're annoying.

Caution, this is the gentle way of 'controlling' the fungus gnats. The herbicide and potatoes do nothing to harm the plant or stress it out too much if at all. If you're garden is really big or the infestation is out of control (or if you're just plain sick to death of them), then you might have to looking into more aggressive techniques. Soil drenches w/Larvaecides like BT kills pretty effectively. but larvae is really hard to kill. I believe poisons strong enough to kill larvae probably aren't great for plants. That the plants don't like it, so to speak, but there are a lot of people who disagree and use BT anyways with no serious (seemingly...) problems.
There's also pyrethrin. It's very good but expensive. Azadirachtin (Azamax) is really good stuff too, but is also expensive.
 

Beansly

RIU Bulldog
(this works best for people with a few plants)

I forgot to add that if you want to some what wipe the slate clean and start over, you can do that by removing the topsoil and replacing it with fresh, clean soil. They lay their larva about a 1/2 inch below the soil line. Sometimes if you move the dirt, you can see a little worm liiting thing wriggling. Because they lay their babies so shallow, they're easy to kill. This is really easy if you happen to have a shop-vac.
First start by taking your herbacide (I use Ed Rosenthal's Zero Tolerance, but anything that kills them on contact) and spraying down the topsoil and killing as many of the crawling and flying ones as you can. After that, if you don't have a shop-vac, take the off all the soil on top of the pot till you get down to the root ball. Make sure you get all of it and make sure to work fast. As soon as you get all of the soil off the top, before you do anything else, get the contaminated soil out of the grow area. Take it far away and put it in a garbage bag and tie it up. Then you just repeat the process with each plant till they're all bare. After that, just put a thick (2- 2 1/2 in.) layer of whatever fresh, clean soil you like over the roots.
For the next few days kill all gnats on sight. Keep the grow space clean. Take off any leaves that are 75% dead. Water your plants early in the morning so by nigh time, the top is somewhat dry. You have to stay on it or else they'll come back though.
 

jpill

Well-Known Member
the cinnamon works ! idk why, probably the chemical make up of it . But i tell everyone about it ! Also the above poster stated DE (diatomaceous earth) also works. It does, DE (diatomaceous earth) will work for most pests. I just use cinnamon because its a lot cheaper and chances are you have some lying around !
 
Top