Fungus gnats? Try these

If you have some really stubborn gnats give these a try. I had an infestation 4-5 years ago and used gnatrol to knock them back and microbelift every couple weeks to keep them away. As unlikely as it may be they seem to have developed a resistance. so I started cycling nematodes in the mix which definitely helped. I usually ordered them from good guys and was mostly happy. However my last 2 orders were complete duds and the gnats started coming back with a vengeance, seeming to give no Fs about the microbelift even at the 5 ml/gal that the manufacturer recommended.


I got an arbico email about a sale and saw these beads so I thought I would give them a shot. It's been 3 nights since I first applied them and there was only one or two flyers per sticky trap when I checked them this morning.

Really happy with these

Just spoon some over the top and water in. They completely dissolve over 3-4 days. For anyone who has dealt with the pain of mixing up the powder or sponges, this makes it real easy. I keep mine in the fridge but when I contacted arbico they told me it's shelf stable at normal room temperature.

How is the product holding up? Are the gnats gone?

Farmer's Hat said:

How is the product holding up? Are the gnats gone?

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He should know by now for sure. I'm still looking for something to put on top of the soil. The spraying is doing the job but I'm still finding new adults on top of the soil all the time.

Samwiseman420 said:

He should know by now for sure. I'm still looking for something to put on top of the soil. The spraying is doing the job but I'm still finding new adults on top of the soil all the time.

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Have you tried Diatomaceous earth? Im testing it tomorrow for the first time. The gnats in my 2x2 tent are sparse. I see a few when I water, then they disappear until next watering.

Farmer's Hat said:

Have you tried Diatomaceous earth? Im testing it tomorrow for the first time. The gnats in my 2x2 tent are sparse. I see a few when I water, then they disappear until next watering.

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The con of DE every watering if not bottom feed will result in need of reapply the DE. Also make sure to wear a respirator protection cause it’s def bad for ur lungs ftw.

Here's how to apply DE with the least hassle: Mix a decent amount in a bucket of soil and from that mixture make a top layer of about an inch in your plant pots. This works better than applying it with a spoon and mixing it directly in the top soil. It's cleaner, the layer is thicker, the DE doesn't waft all over the place and it covers the surface evenly. Bottom watering/feeding from this point on is the best option but you can also attach a soft sprinkler to your watering can and water very gently. The moment your top soil dries out after watering the DE starts working again. 1 application like this lasts weeks and should be more than sufficient to kill an entire infestation.

Chronic1978 said:

Here's how to apply DE with the least hassle: Mix a decent amount in a bucket of soil and from that mixture make a top layer of about an inch in your plant pots. This works better than applying it with a spoon and mixing it directly in the top soil. It's cleaner, the layer is thicker, the DE doesn't waft all over the place and it covers the surface evenly. Bottom watering/feeding from this point on is the best option but you can also attach a soft sprinkler to your watering can and water very gently. The moment your top soil dries out after watering the DE starts working again. 1 application like this lasts weeks and should be more than sufficient to kill an entire infestation.

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Thank you for the advice.I will do that.
Also, it just so happens that I do a very similar thing when I top dress with dry amendments.

Farmer's Hat said:

How is the product holding up? Are the gnats gone?

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They work well. I've ordered more. Every 10 days has worked for me. I still use microbelift for the smaller plants in veg

compassionateExotic said:

The con of DE every watering if not bottom feed will result in need of reapply the DE. Also make sure to wear a respirator protection cause it’s def bad for ur lungs ftw.

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DE is a binder and might contain heavy metals that you dont want to inhale or consume.

The only time I've read of a operation that was failed from to much heavy metals was also using DE. Higher amount than legal limit for commercial use and sale that is.

Private growers generally don't test for heavy metal content and I think it's kind of important to do so if you're growing with rock salts and organics. It's only been documented in organic farming to my knowledge.

I think bacillus thuringiensis extract is both more effective and safer to use for the intended purpose.

Cheers!