Worse fear about growing in soil. Have come true again!

By now most of you know I'm strictly hydro. But I've been growing 6 females in soil 5 gallon smart pots. Was checking on them today And I saw him a fucking Gnat I made it a month and a week without any problems with Gnats until now. I immediately put fly sticky tape traps all in there about 4 of them hanging. I have neem oil extract should I warter them with it next watering? And How do they reproduce anyway do they need a female gnat Because I only saw one and hoping that's the only one. This is exactly why I went to Hydro in the 1st place years ago. I really don't want this to become a huge problem I just started 12 and 12 five days ago So I still have some time to go. I don't want them to be almost done and have a big issue with this. Please help me guys! any advice would be helpful.

fungus gnats are named that because they eat fungus. Fungus only grows where excess moisture is found. Likely your soil is over watered and they hang at top, bottom , and holes. If there is one theres about to be forty.
yellow sticky cards get them good. neem/soap/water spritzed on the top soil or directly on the bastards will kill them. spritz the outsides of your grow bags too. Flip your top soil often, they hate that. dont water with neem if you dont have to. Capn Jacks, BTI/mosquito dips etc are a godsend for this.

feel your dirt pots with dry new dirt, notice the weight, with about four gallons of dirt, now pour exactly one gallon of water in the top all at once. when its absorbed feel the weight again. dont water until the bag is light again, and only use one gallon.

thrips are 10x worse for you....you'll see....

all these come with hydro too btw....

Female gnats lay eggs, they hatch, larvae becomes an adult. The cycle takes about 5-7 days.

Gnats will grow in hydro too. They hang out around the bottom stem.


Pyrethrin applied to the top dirt. Moisten to about 1" deep. Repeat in 5-6 days. Do it again anytime you see an adult flying around. No need to spray the plant. Next time you plant, spray the soil before you start growing. More then likely they came with the soil.

chemphlegm said:

fungus gnats are named that because they eat fungus. Fungus only grows where excess moisture is found. Likely your soil is over watered and they hang at top, bottom , and holes. If there is one theres about to be forty.
yellow sticky cards get them good. neem/soap/water spritzed on the top soil or directly on the bastards will kill them. spritz the outsides of your grow bags too. Flip your top soil often, they hate that. dont water with neem if you dont have to. Capn Jacks, BTI/mosquito dips etc are a godsend for this.

feel your dirt pots with dry new dirt, notice the weight, with about four gallons of dirt, now pour exactly one gallon of water in the top all at once. when its absorbed feel the weight again. dont water until the bag is light again, and only use one gallon.

thrips are 10x worse for you....you'll see....

all these come with hydro too btw....

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Ok just ordered the yellow cards. And imma agitate the top of the soil like you said. About that over watering now that i think about it you might be right with that because I have 5 pots filled with Fox farm and that dries out quickly. But the 6th one i didn't have enough Fox farm left to fill it up and I couldn't wait for any more Fox farm to get delivered to me because The one was so root bound I need to transplant soon as possible. So I went to home depot and just got some organic soil from there and it hold moisture way differently than another 5 pot. I started out watering all 6 at same time but i started to notice the other one with the different soil is always wet when the other 5 are dry. I believe that's where the problem started. They could have been in that cheap soil already too Waiting for moisture for the eggs to hatch. I've been been doing Hydro for 6 years and never had a problem with G nats But I can see and understand that they would like to hang around the rock wall cubes and in the net pots. Thanks for the quick response.

SouthCross said:

Female gnats lay eggs, they hatch, larvae becomes an adult. The cycle takes about 5-7 days.

Gnats will grow in hydro too. They hang out around the bottom stem.



Pyrethrin applied to the top dirt. Moisten to about 1" deep. Repeat in 5-6 days. Do it again anytime you see an adult flying around. No need to spray the plant. Next time you plant, spray the soil before you start growing. More then likely they came with the soil.

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I'm going to try that pyrethrin out Definitely will treat the soil right from the start. They probably came with that soil for the last part i had to fill from home depot. Thanks a lot though So much appreciated!

PuffNpipez said:

I'm going to try that pyrethrin out Definitely will treat the soil right from the start. They probably came with that soil for the last part i had to fill from home depot. Thanks a lot though So much appreciated!

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It'll kill all stages besides the eggs. The second application catches the hatch. Pyrethrin doesn't last long. From what I've seen it'll last about three days. It breaks down fast. I use Southern Agriculture Pyrethrin. I had mosquitos hanging around the plants. It killed those too.

SouthCross said:

It'll kill all stages besides the eggs. The second application catches the hatch. Pyrethrin doesn't last long. From what I've seen it'll last about three days. It breaks down fast. I use Southern Agriculture Pyrethrin. I had mosquitos hanging around the plants. It killed those too.

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owned! thanks

if you do have thrips(I hope you do not trust me) the only thing that will work is "spinosad"

check the underside of the leaves for the larvae.

I had gnats first time this year a couple months ago and heard about capn jacks(spinosad) so I used it on the pots with some success, but then after my soil was good and saturated with it here come the thrips. they seem to stay at the bottom of the pots, if I lift them I see a few smaller ones, larger ones hanging around on over head cords-easy to kill. I think mine eat spinosad.

a week into my first indoor grow i found gnats
top dressed a good 1.5" of perlite on top of my pots which really cut them back.ive seen an increases in them the past few days and realized last night they were chilling in the holes in the bottom of the pots.filled those trays past the pot drainage holes and so far so good. will this not fix the problem if they cant get into the soil to lay or to hatch and get out due to the perlite? yellow sticky traps were put out at the first sign and have caught only two

Lower the amount of watering first and I like to acidfy it too [enzymes, ph down, etc]
Hit with a lil neem and Potassium silicate [AgSil, Pro-Tek, etc]
Can even cover with a little sand or food grade Diatomaceous Earth....

Gnats and thrips are pests and annoying as fuck, but not killers....mites are though imho

You guys are life savers in this case gnat killers lol imma put all these tips to work today moving the Ladies in their new home 5x5x7 tent they filled up the one they in now can't even get in there to water them. Gnats won't stand a chance against me now. Next time imma start off using all these tips so gnat won't have a chance to even get in soil. Thanks again guys I'll keep u posted.

PuffNpipez said:

By now most of you know I'm strictly hydro. But I've been growing 6 females in soil 5 gallon smart pots. Was checking on them today And I saw him a fucking Gnat I made it a month and a week without any problems with Gnats until now. I immediately put fly sticky tape traps all in there about 4 of them hanging. I have neem oil extract should I warter them with it next watering? And How do they reproduce anyway do they need a female gnat Because I only saw one and hoping that's the only one. This is exactly why I went to Hydro in the 1st place years ago. I really don't want this to become a huge problem I just started 12 and 12 five days ago So I still have some time to go. I don't want them to be almost done and have a big issue with this. Please help me guys! any advice would be helpful.

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Gnat nix....2 inches on top of container....problem solved