Gnat larva in soil?

Garbage_bear

Herb Hitman
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So my last grow in the 8x8 tent went horrible. I had to chop early. Gnats just exploded. I put sticky traps and killed hundreds of them. I’ve been treating the soil with bacillus from general hydroponics.

Well my wife said there is probably larva in the soil but she said I cannot but any more soil cause we can’t afford it at this time.

So what can I do to save this soil? Living soil. I am letting the dirt fully dry out with fans but I still see gnats when I go in there. Not many but they still there! I’m not growing in there at the moment. I have a bunch of Jager plants that will need to go in that tent in the next month or so.

What can I do to save this soil and make sure I don’t have gnats again? Oh and here is a picture of Mark Zuckerberg surfing for your pleasure:

IMG_8971.jpeg
 
DE as mentioned.
Misting it with diluted orange oil will do the job too but will have to wait for the oil to degrade a few days after before sticking plants in it.
Depends on how much soil we're talking here but if possible, something like a tub or kiddie pool and spread the soil out letting the Sun hit it and dry it. The UV alone should kill the larvae.
 
So my last grow in the 8x8 tent went horrible. I had to chop early. Gnats just exploded. I put sticky traps and killed hundreds of them. I’ve been treating the soil with bacillus from general hydroponics.

Well my wife said there is probably larva in the soil but she said I cannot but any more soil cause we can’t afford it at this time.

So what can I do to save this soil? Living soil. I am letting the dirt fully dry out with fans but I still see gnats when I go in there. Not many but they still there! I’m not growing in there at the moment. I have a bunch of Jager plants that will need to go in that tent in the next month or so.
Listen to the experienced guys. Only sharing an experience I had with gnats in some large ornamental plants last Fall. At the time, Mosquito Bits were probably the most common remedy popping up in my search results. Allowing the top layer to dry back, like you are already doing, was another recurring bit of advice. I had read that Neem Oil can be effective and I had some on hand. So I watered in the Neem oil one time and dried back the top layer of soil. Adult gnats died off after a couple of days and no more made it to adult stage. Might have just been lucky, but the gnats went from heavy population to zero.

This guy has landed on Neem Meal (cake) for his fungus gnat control. He claims it's easier on the soil than the oil version, due to emulsifiers used. I know it's an ingredient in BAS 3.0 living soil recipe. It was also an ingredient in the living soil recipe I followed when building soil for my outdoor grow sites. So, this may be something to consider:


What can I do to save this soil and make sure I don’t have gnats again? Oh and here is a picture of Mark Zuckerberg surfing for your pleasure:

View attachment 121298
Is the Zuck transitioning into Michael Myers?

Good luck! If you can, let us know what works for you. Sounds like a common issue that many of us are gonna run into. I included in some leftover Neem meal when I re-amended my outdoor soil after this years harvest, but I doubt I'd be able to tell how effective it is compared to a controlled indoor environment. I just bought some BAS Craft Blend to re-amend the BAS 3.0 with for my next indoor grow. Your post is gonna make me look and see if Neem meal is in there or I should buy some to mix in with the Craft Blend and worm castings 👊.
 
So my last grow in the 8x8 tent went horrible. I had to chop early. Gnats just exploded. I put sticky traps and killed hundreds of them. I’ve been treating the soil with bacillus from general hydroponics.

Well my wife said there is probably larva in the soil but she said I cannot but any more soil cause we can’t afford it at this time.

So what can I do to save this soil? Living soil. I am letting the dirt fully dry out with fans but I still see gnats when I go in there. Not many but they still there! I’m not growing in there at the moment. I have a bunch of Jager plants that will need to go in that tent in the next month or so.

What can I do to save this soil and make sure I don’t have gnats again? Oh and here is a picture of Mark Zuckerberg surfing for your pleasure:

View attachment 121298

Mosquito bits, 100% effective, complete eradication after two or three applications (breaks the lifecycle). Use with yellow sticky cards for control and monitoring.

Screenshot_20251222_132459_Chrome.jpg

🪰
 
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The cause of gnats is overwatering..
The remedy is a h2o2 soil drench and a dry top layer of DE.
The hydrogen peroxide has a extra oxygen molecule that acts like a radical agent and destroys soft body bugs..
The Diatomaceous Earth has sharp edges that removes the bugs protective wax and then dehydrated them..

This method works...
 
Does it have any negative effects on the plants or on people?
If you're worried about negative effects, the last thing I would bring into my environment is DE.

Mosquito bits are so benign you can use them in your horse's watering trough.

Once the mosquito bits have done their job initially, use them once in a while for maintenance. Should be a schedule on the bag.
Good luck!
 
What is that? The picture is too blurry to make out what it says.
Nematodes in @steamroller picture . Rove beatles and predator mites work too. Nematodes ship better in the winter. I have had problems with the mosquito bits working for me in the past.i think the active bacteria in the bits have a hard time setting up shop in the soil when you have alot of other biology already there.thats not a fact just kinda why I thought why I had problems . If you use sticky traps for the the adults and Nematodes in the dirt it will break thier cycle.i have had that work for me at least, in the past. The Nematodes work great.
 
If you're worried about negative effects, the last thing I would bring into my environment is DE.
Looks like there are several ways to successfully eliminate gnats, but I have to ask: What are the negative effects that you have experienced using DE?

I've haven't tried to use DE against gnats, but I do use it regularly for our layers in the chicken run and mixed with peat moss for their dust baths.

I also use it for pest prevention in my outdoor garden. I have to be careful not to use it as a foliar application where pollinators can be harmed, but I mainly use it as a soil dusting anyway. Plus, it provides nutrient content when mixed into the soil. I don't believe I'm using enough to impact earthworms. At least, there always seems to be a high population of them.

I don't want to get it in my eyes or lungs, but that would be pretty hard to do unless I was tossing it into the air with the wind blowing into my face, lol. It's supposed to be a skin irritant, but I don't take any special precautions and haven't noticed anything.
 
Looks like there are several ways to successfully eliminate gnats, but I have to ask: What are the negative effects that you have experienced using DE?

I've haven't tried to use DE against gnats, but I do use it regularly for our layers in the chicken run and mixed with peat moss for their dust baths.

I also use it for pest prevention in my outdoor garden. I have to be careful not to use it as a foliar application where pollinators can be harmed, but I mainly use it as a soil dusting anyway. Plus, it provides nutrient content when mixed into the soil. I don't believe I'm using enough to impact earthworms. At least, there always seems to be a high population of them.

I don't want to get it in my eyes or lungs, but that would be pretty hard to do unless I was tossing it into the air with the wind blowing into my face, lol. It's supposed to be a skin irritant, but I don't take any special precautions and haven't noticed anything.
I've never used it, I wouldn't have it in my INDOOR environment. Inhalation of DE can cause health issues.

I've been dealing with respiratory issues for two decades from cumulative chemical and solvent damage from a business I ran in the last century, the last thing I'd use is a substance that could cause respiratory issues, especially when a safe and effective alternative exists.

AI: "Diatomaceous earth (DE) is generally considered safe for indoor use when applied correctly, especially food-grade DE. However, precautions should be taken to avoid inhalation and skin contact, as it can cause irritation and respiratory issues."
 
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I've never used it, I wouldn't have it in my INDOOR environment. Inhalation of DE can cause health issues.

I've been dealing with respiratory issues for two decades from cumulative chemical and solvent damage from a business I ran in the last century, the last thing I'd use is a substance that could cause respiratory issues, especially when a safe and effective alternative exists.

AI: "Diatomaceous earth (DE) is generally considered safe for indoor use when applied correctly, especially food-grade DE. However, precautions should be taken to avoid inhalation and skin contact, as it can cause irritation and respiratory issues."
Thanks and excellent point on the inhalation risks. I work in an industry that has chemical hazards, as well. In my opinion, safety still isn't where it needs to be, but I've seen major improvements over the last 30yrs. Stories from the folks 30 years ahead of me are the stuff of nightmares, compared to what I've seen.

Not chemical, but I had some experience with asbestos in the Air Force. Stationed on and old base that was army before going to the air force. They use to send us in with zero protection to remove asbestos before renovating the old buildings using circular saws and anything else we could to rip it out. Dusty, as you can imagine. None of us doing the work knew any better. Didn't even know it had asbestos in it. Someone, no idea who, actually called OSHA on the Air Force when I was on one of these assignments. OSHA showed up and shut the job down. Made us strip down naked and hosed us off in portable showers. Put us in Tyvex suits, before releasing us to go get dressed. After that we went through all kinds of training on isolating the work areas with plastic sheeting and installing portable filtered intake/exhaust systems, encapsulating less-friable floor tiles containing asbestos with this sticky citrus-based liquid to reduce the risk of it becoming airborne, respirators and suits, building plastic lined containers to ship off the asbestos to where put in troughs and submerged in water...

I've come to rely on DE for a few specific purposes and was half afraid you were going to bring a new (to me) concern that was going to send me on a hunt for alternatives, lol.

Talking about the hazards of DE made me randomly wonder if it was a contributing factor in Vito's death, lol? A review of the clip shows the sprayer was liquid. Guess it could have had DE mixed in for a wet and dry foliar application ;smoke

 
Thanks and excellent point on the inhalation risks. I work in an industry that has chemical hazards, as well. In my opinion, safety still isn't where it needs to be, but I've seen major improvements over the last 30yrs. Stories from the folks 30 years ahead of me are the stuff of nightmares, compared to what I've seen.

Not chemical, but I had some experience with asbestos in the Air Force. Stationed on and old base that was army before going to the air force. They use to send us in with zero protection to remove asbestos before renovating the old buildings using circular saws and anything else we could to rip it out. Dusty, as you can imagine. None of us doing the work knew any better. Didn't even know it had asbestos in it. Someone, no idea who, actually called OSHA on the Air Force when I was on one of these assignments. OSHA showed up and shut the job down. Made us strip down naked and hosed us off in portable showers. Put us in Tyvex suits, before releasing us to go get dressed. After that we went through all kinds of training on isolating the work areas with plastic sheeting and installing portable filtered intake/exhaust systems, encapsulating less-friable floor tiles containing asbestos with this sticky citrus-based liquid to reduce the risk of it becoming airborne, respirators and suits, building plastic lined containers to ship off the asbestos to where put in troughs and submerged in water...

I've come to rely on DE for a few specific purposes and was half afraid you were going to bring a new (to me) concern that was going to send me on a hunt for alternatives, lol.

Talking about the hazards of DE made me randomly wonder if it was a contributing factor in Vito's death, lol? A review of the clip shows the sprayer was liquid. Guess it could have had DE mixed in for a wet and dry foliar application ;smoke

I remember my grandmother spraying a cloud of that stuff in the outhouse before sending us in before bed. I think the spiders and mosquitoes would have been better. 🤣
 
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