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How do I deal with fungus gnats? I've had SO many suggestions.

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How do I deal with fungus gnats? I've had SO many suggestions.

Growth 91 Replies 40,167 Views
Page 3 of 5 · Replies 41–60 of 92
#41
Redneckx said:
I prefer giving them as much water as possible right until a little drain comes out, do they need too long to dry out to get some oxygen? How much water do you give your plants?
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Typically half a gallon every few days
 
#42
I've tried EVERYTHING..... and only THIS has worked, like dropping napalm all over some vietcom.

PXL 20231121 002507827
 
#43
ArtfulCodger said:
Diatomaceous earth, top dressed and worked in a little bit to kill the crawlers. Yellow sticky traps to get the fliers. That's what I do, anyway.
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Hers my method lol

I mix in DE with my soil but I also like to keep a small cup of soil with about an inch of perlite on top, then I put a bunch of DE on top and shake the cup a shade to let some of the DE settle in, I’ll dip the bottom of that pot in water every 3-4 days to keep moisture in it, when the gnats stop by it’s bye bye time you’ll start seein the suckers dead on the tent floor 😁

The little cup in the middle of the plants I keep the cup going for the whole grow

If it gets overwhelming I put 2” of perlite on top of my soil in my pots and do the same thing when you water the gnats come up for air, and when they do they have to go right through the DE on top to escape that method worked well when I had 3 weeks left on a grow, saw someone say it as a tip to someone and it worked so damn well haha
 

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#45
gnats are easy peasy.

they live/spawn/larvae in the soil and the adults fly.

go buy a $2?$3? pack of those hanging sticky strips. use them all and hang them all around in your space. That takes care of the flyers.

Now go to your local box store or amazon and get a concentrate of Bacillus Thuringiensis (BT). Mix it at 1 Tablespoon per gallon and soil drench your pots. that takes care of the egss/larvae. life cycles interrupted.

problem solved. no harsh chemicals needed
 
#46
Growth said:
This is my 4th grow and first time getting fungus gnats. I've tried letting the soil dry up it's barely "moist" knuckle deep at this point but I don't want to under water them.

I've tried crushed eggshells on top of the soil.
I've tried fruit fly traps with apple cider vinegar.
I've tried spraying the soil and leaves down with diluted alcohol spray.
I have fans blowing on them.

I'm growing auto-flowers and I'd say they're almost halfway done. Are these things going to kill my plants? How do I get rid of them?
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Put teaspoon of baking soda in spray bottle, spray Lower half of plants and soil
Growth said:
This is my 4th grow and first time getting fungus gnats. I've tried letting the soil dry up it's barely "moist" knuckle deep at this point but I don't want to under water them.

I've tried crushed eggshells on top of the soil.
I've tried fruit fly traps with apple cider vinegar.
I've tried spraying the soil and leaves down with diluted alcohol spray.
I have fans blowing on them.

I'm growing auto-flowers and I'd say they're almost halfway done. Are these things going to kill my plants? How do I get rid of them?
Click to expand...
Mix teaspoon of baking soda in spray bottle
 
#47
Kennethcherrynewton said:
Put teaspoon of baking soda in spray bottle, spray Lower half of plants and soil

Mix teaspoon of baking soda in spray bottle
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Dont use baking soda, baking soda is sodium bicarbonate... sodium in very tiny ammounts can be good for the roots but thats WAY too much sodium.
 
#48
Growth said:
This is my 4th grow and first time getting fungus gnats. I've tried letting the soil dry up it's barely "moist" knuckle deep at this point but I don't want to under water them.

I've tried crushed eggshells on top of the soil.
I've tried fruit fly traps with apple cider vinegar.
I've tried spraying the soil and leaves down with diluted alcohol spray.
I have fans blowing on them.

I'm growing auto-flowers and I'd say they're almost halfway done. Are these things going to kill my plants? How do I get rid of them?
Click to expand...
 
#49
Eledin said:
Dont use baking soda, baking soda is sodium bicarbonate... sodium in very tiny ammounts can be good for the roots but thats WAY too much sodium.
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BAKING SODA IS USED TO RAISE PH IN WATER,ITS. NOT HARMFUL
 
#50
Kennethcherrynewton said:
BAKING SODA IS USED TO RAISE PH IN WATER,ITS. NOT HARMFUL
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I think growers are worried sodium can build up over time and damage the soil. I think it would take a lot of that solution sprayed onto the plant before it would affect plant growth/soil. However, you have options available that dont have any possibility of this?
I take it that it has worked for you without any ill effects so it is nice to have this treatment should circumstances dictate its use.
IIRC the Romans would sow salt into conquered people's farm land to render it sterile which allowed them to further subjugate the conquered .
 
#51
Used DE multiple times now and it drys the soil even faster.
Eggs are visible after watering but they should be all dead, DE is a good way to go.
 
#52
Kennethcherrynewton said:
BAKING SODA IS USED TO RAISE PH IN WATER,ITS. NOT HARMFUL
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I use it myself, in very small quantities. Have you ever raised your ph with baking soda? It takes very little of it. Its like saying that you spray the soil with phosphoric acid and its okay because its used in PH down. A teaspon in a spray bottle is WAY too much, but we can agree to disagree and thats okay too. Im not saying youre gonna kill the plant but the roots are not gonna like it IMO and youre raising the ph of the soil by doing that.
EDIT: I must add that I dont know for sure if that ammount would cause damage to the roots, I guess it depends on how often and how many times you use it. If its only once maybe its harmless but I personally wouldnt do it. Baking soda is 27% salt.
 
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#54
DE was too messy and caused soil issues. Neem gave me a headache and smelled awful, also leaving a taste in my mouth after spraying. If that was my only option I’d just junk the grow and start over. That shit was awful. Bti in any given form, together with sticky traps and judicious watering has always worked well for me. One particularly bad infestation that I didn’t catch early enough required predator mites. Worked great but a very pricey route.
 
#55
Eledin said:
Diatomaceous earth does work... and its cheap as hell, who said it doesnt work? When you mix it with the top layer of soil youre killing ALL the larvae and eggs and for the adults is a matter of time aswell, they live on the substrate even if they fly away thats where they come back to reproduce. That said if you have another pot close by with substrate that youre not using theyre just gonna move there until they can return to your tent. If DE doesnt work for you guys, youre doing something wrong. Years ago I had a really bad one, tried spraying the fuckers with neem oil, potassic soap, hydrogen peroxide and even alcohol at some point, needless to say the plants were begging me to stop... then I used diatomaceous earth, took me a couple of tries but when you get the hang of it is super easy and the cheapest option and it also benefits the plants, its not just a pest control product. I had a pot with arlite in it, I found that the fuckers went to the arlite pot while thay waited to re-colonize my substrate, just keep away anything that can serve them as a home and with DE you dont need anything else...
EDIT: As for outdoors it will prevent any non-flying insect from getting into your plants. Outdoors you will never get rid of them you can only control them, they have plenty of other places to reproduce and come back but diatomaceous earth will 100% prevent them from putting larvae in your soul to munch on your roots.
IMPORTANT: I said it already but its really important to cover any crack in the soil, specially on the sides of the pot, they can live on the sides by going deeper if you dont cover everything well, thats where most people fail with DE, if you leave them a couple of inches of space is enough for them. One single female con put up to 200 eggs (thats why it can get out of control very quickly indoors), even tho not all of them make it to adults but you can see why it wont work if you dont cover everything well. Or if you just sprinkle it on top, you need to mix it with the top layer of the soil covering EVERYTHING. I put extra on the sides cause I use textile pots and its very easy for cracks to form on the sides.
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Just got some yesterday. I genocided those mother fuckers. all gone today
 
#56
Growth said:
This is my 4th grow and first time getting fungus gnats. I've tried letting the soil dry up it's barely "moist" knuckle deep at this point but I don't want to under water them.

I've tried crushed eggshells on top of the soil.
I've tried fruit fly traps with apple cider vinegar.
I've tried spraying the soil and leaves down with diluted alcohol spray.
I have fans blowing on them.

I'm growing auto-flowers and I'd say they're almost halfway done. Are these things going to kill my plants? How do I get rid of them?
Click to expand...
Next run start with a systemic pesticide. I use formula 203 (light blue one) it's all natural and won't effect your girls in any negative way. Use the red 203 for a root drench when your actually infested which sounds like you are lol. It's simply oil's that deture pests from eating at all. It builds in the cell walls and gnats will avoid it.. just remember that once you have gnats or most any pests, there's no real cure. All you cam do is control em. Get yourself some yellow sticky pads and put em close to the soil and just under your canopy if possible. This should give you an idea as to how bad the infestation is.. hope this helps. Also be aware that I've been growing 25 years and have battled many pests but mostly fungus gnats lol!
 
#57
Ryguy45 said:
Next run start with a systemic pesticide. I use formula 203 (light blue one) it's all natural and won't effect your girls in any negative way. Use the red 203 for a root drench when your actually infested which sounds like you are lol. It's simply oil's that deture pests from eating at all. It builds in the cell walls and gnats will avoid it.. just remember that once you have gnats or most any pests, there's no real cure. All you cam do is control em. Get yourself some yellow sticky pads and put em close to the soil and just under your canopy if possible. This should give you an idea as to how bad the infestation is.. hope this helps. Also be aware that I've been growing 25 years and have battled many pests but mostly fungus gnats lol!
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luckily FGs are the least of our farm's worries. At first, I even thought they were sort of cute. Then I had a huge FG outbreak in the past, and from then on, the only good FG is a dead one. They were everywhere. My kitchen, bathrooms, bedroom. I thought they were floaters until I realized that the amount of floaters seems very excessive.. LMFAO
 
#58
Ryguy45 said:
Next run start with a systemic pesticide. I use formula 203 (light blue one) it's all natural and won't effect your girls in any negative way. Use the red 203 for a root drench when your actually infested which sounds like you are lol. It's simply oil's that deture pests from eating at all. It builds in the cell walls and gnats will avoid it.. just remember that once you have gnats or most any pests, there's no real cure. All you cam do is control em. Get yourself some yellow sticky pads and put em close to the soil and just under your canopy if possible. This should give you an idea as to how bad the infestation is.. hope this helps. Also be aware that I've been growing 25 years and have battled many pests but mostly fungus gnats lol!
Click to expand...
Could you post a link for the formula 203 please, can't find it.
 
#59
storz said:
luckily FGs are the least of our farm's worries. At first, I even thought they were sort of cute. Then I had a huge FG outbreak in the past, and from then on, the only good FG is a dead one. They were everywhere. My kitchen, bathrooms, bedroom. I thought they were floaters until I realized that the amount of floaters seems very excessive.. LMFAO
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I know how that feels like and I just had it once and not that heavy, tbh i hate gnats anyway but the horde made me crazy killed all every and they return the next day. Coudn't sleep well.
 
#60
Howdy diatomaceous earth and cover vent holes in tge bottom the diatomaceous earth choos tge uo and drys them out when they crawl through it but that's for adults you still have larvae in the soil nematodes i myself use rove beetles and predator mites for fungus gnats ✌️
 
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