Fly strips can get just about anywhere come with about 6 in package and you can use D-E or sand on your soil to kill gnat’s in soil
Also neem seed meal.
I used this a couple weeks ago on my worm bins to try to combat some fruit flies or fungus gnats that I had going in there. Between the one top dressing with this and probably the colder weather, it seems to have knocked them out pretty good.
The nitrogen in it is water insoluble so I don’t think it would mess with your fertilizer ratio too bad. If I see the bastards in my flower tent I don’t think I’d hesitate to use it.
NEEM oil spray works well for foliage for immediate results, every two weeks and if infested do it every week on same schedule and schedule on bi-weekly.
@Cannaman22 there’s a difference between neem oil spray and neem seed meal didn’t know if you known that or not
Thanks for your input.
For fungus gnats BT is the way to go. Use the Israeli variant it works better I have found. It shreds the knats and it doesn’t make your buds smell like Neem oil. I also second the sand or D. Earth to make a barrier. But barriers only work if you cannot see any soil. Cover the top layer cleanly. Do not leave soil doors for them. Also, put blue painters tape over any drain holes open to the side for a week during treatment. Or else those fuckers will go in the drain holes and the larve will burrow all the way up the side of the pot. Don’t water during this unless they wilt.
I used to spray heavily with neem oil as a pest preventative. Like an IPM plan before I ever caught bugs. But I haven’t done that for probably five or six years now. I think the Neem oil if applied the flowers, even early in flower, makes all your buds taste like hint of Neem. But most importantly, a lot of studies are showing that Neem isn’t necessarily good for humans to have in our bodies in high doses. I have seen lots of hypothesis going around that it could linked to the HMS (hyperemesis syndrome) causing uncontrolled vomiting with cannabis use. No conclusions yet that I have seen anywhere….
So I save it in my arsenal, but it’s usually the last thing I use to spray. I’ve heard good things using the seed meal in soil, but I bet you have to put it in your mix and top dress regularly to be effective. Microbes will turn it into plant food as fast as the other amendments in my opinion.
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this is one of the reasons I decided to investigate and develop an all natural, non-gmo organic bt based concentrate. Very few products can get sprayed on flowers without affecting taste / quality. I also add a layer of silica sand and then fishtank gravel to make the upper barrier. The gravel helps keep the doors closed when watering. I would also get a gnat here and there when I purchased new organic soil for substrate or even my compost from the garden. My solution addresses gnats, flies, thrips, etc but becasue of the BT, is targeted so beneficial’s are not harmed . I concentrate on nano micelles so it also effectively deals with all types of mold and can e used as a final rinse / cleanse at harvest (great for outdoor grows)
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I have had good luck with powered cinnamon sprinkled on top of the soil.
The cinnamon from Ceylon is supposed to work best.
Sorry for reviving an old topic, but I have some gnats so I was looking for info on the topic and found this. Neem is overrated, not because it’s ineffective, but because effective products are not so common as you might think. All Neem Oil products are not alike and chances are, if you’ve had a bad result from Neem Oil, it’s because it was an ineffective one. There is a very good video on this here: Why Neem Oil Doesn’t Always Work! The Science Of Neem Oil For Plants & Soil | Scientist Explains - YouTube . The heart of the matter starts around 2 minutes into the video. The active ingredient in Neem only works if the Neem was cold-pressed.
And even if it is cold pressed, it can still be ineffective. You would have to learn about the true process of “cold pressing”. Many mfg’s state cold presses but an expeller agent is often used and the chems in expressing agents really mess the product up. Same goes for almost all of our vegetable oils.
For gnats, the easiest is just silica sand (crushed quartz mostly) cover over the substrate, then a layer of gravel (pea or even fish tank) so when you water it does not cause the silica surface to break. Adults dies off in a bout 3-4 days.
Ths does not address eggs / larvae in the soil but they cannot emerge
This is one of the reasons behind my formula, it can be used to saok the soil and the BI and other additives (all organic, non-gmo) address gants, and other critters, mold, etc, while leaving beneficials untouched
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And even if it is cold pressed, it can still be ineffective. You would have to learn about the true process of “cold pressing”. Many mfg’s state cold presses but an expeller agent is often used and the chems in expressing agents really mess the product up. Same goes for almost all of our vegetable oils.
For gnats, the easiest is just silica sand (crushed quartz mostly) cover over the substrate, then a layer of gravel (pea or even fish tank) so when you water it does not cause the silica surface to break. Adults dies off in a bout 3-4 days.
This does not address eggs / larvae in the soil but they cannot emerge
This is one of the reasons behind my formula, it can be used to saok the soil and the BI and other additives (all organic, non-gmo) address gants, and other critters, mold, etc, while leaving beneficials untouched