Can you overdo it with Bacillus thuringiensis? (mosquito dunks)

Struggling with fungus gnats. Last week, I sprinkled a pack of Bacillus thuringiensis israelensis (this product) on the top of my soil before watering thoroughly, then spraying the clover I'm using as a living mulch with neem oil (this product). Last time, I split one 0.2 oz packet between my four plants, thinking that would do the trick. It got rid of most of them, but there are still buggers hanging around. Today I noticed more. I believe the gnat larvae has caused/is causing leaf deformations on one of my plants.

So my question is - how much more can I apply? The product I'm using appears to be mosquito treatment for fountains, but I don't believe it would make a difference because the only active ingredient is Bacillus thuringiensis israelensis all the same.

How much more should I apply? The directions recommend one 0.2oz pouch per 50 sq. ft. of water infested with mosquito larvae. Would it be worth it to try dissolving some in my 2 gallon watering can? Can you overdo it with Bacillus thuringiensis?

I find it will never completely eleminate them but works good to keep them at bay. Get yourself some nematodes and you'll be happy. Try letting the bti sit in water longer before adding it. Extra bti is usually useless.

Also try letting your soil dry a bit more than usual if you can.

It almost seems like they become more resistant to bti after awhile i find aswell. Just my opinion.

I use mosquito dunks(bti) combined with nematodes. No gnats ever again

Thanks for the tip! I was also thinking I'd replace the living mulch of clover with some straw. I'm thinking the clover is providing the perfect conditions for the fungus gnats to gnaw on shallow roots.

If you actually want to be rid of them move to Permethrin SFR 36% as a soil drench. But if you've started naming them don't listen to me.

crittertime said:

Thanks for the tip! I was also thinking I'd replace the living mulch of clover with some straw. I'm thinking the clover is providing the perfect conditions for the fungus gnats to gnaw on shallow roots.

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I'd keep the living clover layer and deal with the gnats. Did you just start a new batch of no-till?

Bti, hypoaspis miles, nematodes, rove beetles are all good in soil. I just use EWC to get them, but you can buy them separately in higher concentrations. I haven't seen a gnat in over 2 years using the same soil.

PadawanWarrior said:

I'd keep the living clover layer and deal with the gnats. Did you just start a new batch of no-till?

Bti, hypoaspis miles, nematodes, rove beetles are all good in soil. I just use EWC to get them, but you can buy them separately in higher concentrations. I haven't seen a gnat in over 2 years using the same soil.

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Yes, but not intentionally as no-till. I've got a few 7-gallon bags in a super soil I made months ago, with a clover mulch layer. My plants are still in veg and have adjusted well to the soil; they're super dark green, but seem happy enough (besides the gnats.)
What do you do about high nitrogen levels in your soil once you switch to flower?

crittertime said:

Yes, but not intentionally as no-till. I've got a few 7-gallon bags in a super soil I made months ago, with a clover mulch layer. My plants are still in veg and have adjusted well to the soil; they're super dark green, but seem happy enough (besides the gnats.)
What do you do about high nitrogen levels in your soil once you switch to flower?

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I'd lower the N, and add more P and K amendments if your doing organics like I'm guessing if you are going into flower. You have to be ahead of the game though. Organics take awhile to break down, so you kinda have to give it what it wants before it actually wants it. I'm still learning though.

PadawanWarrior said:

I'd lower the N, and add more P and K amendments if your doing organics like I'm guessing if you are going into flower. You have to be ahead of the game though. Organics take awhile to break down, so you kinda have to give it what it wants before it actually wants it. I'm still learning though.

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Right, so how do you lower N when it's all right there in the soil?

Should I repot into a lower nitrogen soil? My plants haven't entirely filled out their bags yet so it would be possible to knock out the super soil they haven't reached yet, and replace it some soil lower in nitrogen. I just wonder if the transplant shock would do more harm than good.

crittertime said:

Right, so how do you lower N when it's all right there in the soil?

Should I repot into a lower nitrogen soil? My plants haven't entirely filled out their bags yet so it would be possible to knock out the super soil they haven't reached yet, and replace it some soil lower in nitrogen. I just wonder if the transplant shock would do more harm than good.

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I'm just saying don't give it more N. I wouldn't worry about taking any out or anything like flushing shit. Just chill and don't give it more high N amendments.

I got rid of my fungus gnats with Bti and nematodes, powerfull mix.

crittertime said:

.... The directions recommend one 0.2oz pouch per 50 sq. ft. of water infested with mosquito larvae. Would it be worth it to try dissolving some in my 2 gallon watering can? Can you overdo it with Bacillus thuringiensis?

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The flyers can roam around for weeks.
The directions recommend every 7 days until under control, then change to 14 days. Don't have to add it all.
Soak overnight, water evenly, throw the soaked wood chips on top
Permethrin speeds up their demise, keeps the flyers from returning, good to tank mix together.