So I've seen a couple of Fungus Gnats flying around my plants, and I do kill them when I seem, I just need something to prevent them laying eggs in my soil and killing my roots.
Been having this same problem myself. I have tried neem misting the soil but they just push further down until the coast if clear. I also saw where folks say to put a container with apple vinegar by the plant and that will attract the adults where they wiIll drown. It worked somewhat but I still had them. I also was told to put sand on the surface of the soil and they will die because they need moisture to live. I dont know how to do this while still cultivating so I have not tried it yet. I recently saw a few products in a hydro store that are supposed to have good success. Gnat sticks are like sticky paper but you can stand them up and the yellow color attracts them. I put two in with a clone mother last night and already I have a bunch that are stuck to them. The other product is called "mosquito dunks". These are for keeping mosquitoes out of stagnant water but I was told to break up the "dunk" and scatter it around the plant's soil surface and it drives out the pests. I dont know enough about this product to say if it works. I might try it though. It also comes in a granular form that wont have to be broken up. I hope this helps you out.
i myself have been battling these little fuckwits too. neem spray and yellow sticky strips have helped. not sure if i had em that bad cos my sticky strips only caught three and i havnt seen any in a few days now. i would highly recommend neem spray as a repellent althoughthe stuff stinks like hell itself!
forgot to add that neem doesnt kill them but it stops them from feeding and reproducing and basically stops them living altogether. that means you have to apply throughout one life cycle of the gnat(app 2 weeks) spray every 3-4 days for two weeks and that will get rid
If you're growing in soil, you're in luck cause this is a sure-fire cure. Go to the local nursery and get some Diatomaceous Earth. DO NOT USE THE POOL FILTER STUFF, it won't work! Must be garden grade and say's to use for crawling insects. Sprinkle a light layer across the top of the soil on all the plants. When you water, the stuff will wash down into the soil, that's OK, just put another layer on top after you water. Wait till the soil is not too wet though. This stuff will cut and eventually kill the adults as they crawl through it. As it gets washed down, some residue might show on the saucers, leave it there. As it saturates the soil, the larvae will also get cut and die. You still see more flies for a week or so, it might not look like it's gonna work but it will. Soon you'll see many dead adults lying around the floor and fan intakes. If there are lots of adults you can also vacuum them up. That's easiest to do right when the light turns on, they are sluggish and tend to go up to the light. A few minutes and you can get 100's of them, but that will not solve the problem. Use the DE!! Goodluck
azatrol will knock them out after a few applications from personal experience. i used 5ml/gal once a week for about 3 weeks and am gnat free. on a side note i also had spider mites for the first time recently. might wash will knock spider mites out in no time if you ever happen to get them
I just read about using DE also. Do you notice any affect, good or bad on the plant? Will it have to be flushed after a while?
DE is totally organic, no need to do anything but use it. It stays in the soil and is inert. The "good" effect on the plant is that it stops the gnats
cheap and efficient method of getting rid of fungus gnats in soil: 1) put 1 inch dry sand on top of plant soil (this prevents adults from penetrating soil and laying eggs) 2) buy some mosquito dunks (they go a longggg way and can be used over and over after dried out) put them in your watering cans and let them sit for a bit before watering. this contains BTi which is a bacteria that kills the gnat larvae in the soil. 3) place yellow sticky trips near your pots for the adults to fly into to get rid of the adults these 3 steps virtually eliminated all fungus gnats for me
I am having them again. The first time I put perlite as a layer on soil. Also remember that the will lay in the holes under the pot. I put a layer perlite now due to that. Really hope I can knock them out this time. So humid though. I had two this morning that the first oval leaves were yellow, so I knew they would die. When I got them out, the soil smelled like ammonia. Also found no worms or larvae. I suppose I should make sure to add more perlite. Even though I use a lot already. Should just grow them in perlite lol
I had gnats 2 grows ago. When I fed my ladies mollasses they were gone. Dont know if the mollasses had anything to do with it but they disappeared after that. Sent from my SPH-L710 using Grasscity Forum mobile app
Gnatrol is a good product when it comes to killing the larva in the soil. You can grab a bottle on amazon for ten bucks. I just got done with my battle against the gnats using a combination of the gnatrol, DE, and yellow fly traps and it worked like a charm. It's important to go after the larva because they're what do the damage by eating the root hairs.
vinegar doesnt do shit... a cup of water does the same as vinegar. I dont know why the internet insists its the "best" way to get rid of them. One thing to do is to make sure your soil dry's out more before watering. They need the moisture to live. Thats one reason the sand works wells, it drains so fast, they dont like the dryness. as for getting rid of them? i had them 2 weeks ago, let my plants go to almost wilting from not watering, gnats are gone.
I was content to coexist after many failed attempts to exterminate them all and I didnt see any damage to the plants. But looking at my harvest I now see gnats stuck to the trichomes!! The buggers are so small its so time consuming picking them all out, so frustrating. These guys will be no friends of mine come next grow, they can expect rambo.
@[member="chep42"] I water with molasses every other time and the gnats don't seem to care, if anything i would be they like the sugar.