Help with Fungus Gnats

SO I've read every post on here and basically dried my plants out for 5 days I have been manually killing all adults I can find. Along with fly strips and paper plates cut out to cover the tops of the pots. Today is the first day I can not find a single adult flying around my grow room or in the soil. My first few leaves did begin turning yellow which I hope they can recover. MY questions is should I begin watering them again or can the larvae be laying dormant waiting for water to bring them back?
 

guy incognito

Well-Known Member
I found once I had fungus gnats they were near impossible to kill off. I still have them in my house plants and floating around my house, but not a single one in my grow room anymore. I bought a bag of sand and covered all my plants with about an inch of it. I also hung a couple pest strips to catch the flying ones. The sand really interrupts their life cycle. No matter wet or dry those fuckers dont mess around in my room any more.
 

mcpurple

Well-Known Member
i had them and this is what i did and it worked great. 1. let the soil dry up but not to the point of stressing your plant. 2. water the soil with neem oil it is all organic and will suffocate any larva.3. keep killing the flyers. 4.i did not do this one but it is a good idea to do. get sand and not sand from the ocean they sell sand for plants at hydro stores and gardening centers. place about a 1/2 inch layer on top of your soil. 5 stop over watering or leaving runoff in the treys under the pots.
 
Ok I purchased the neem oil from petco they had it labeled as 100% organic neem oil for fleas and ticks how should I dilute this for use?
 

del66666

Well-Known Member
5ml, couple drops dish liquid, 2 litres of water, shake n spray, shake often, use at lights out only, spray pots and soil too
 
i used 2 parts iso alchohol to 1 part water and sprayed constantly throughout the day for about a week, hung fly strips, turned temps down as much as possible, used dishsoap mix and poured in trays, ordered some monterey insect spray with spinosad,https://www.bwgs.com/details.aspx?sku=MGI700&AC=1
heard good things about this stuff. I seem to have them under control now, the main thing is to stay on top of them, it's a war.
 

jawbrodt

Well-Known Member
^Go with sand, or you'll still have them around. Neem might suffocate them, but, it's the ones that don't suffocate, that you have to worry about. I swear they love eating neem, and invite all their friends and family, to come enjoy the feast. Afterwards, they'll get drunk and have a fuckfest, re-populating quickly. :lol:
 

reh420

Member
I had both my mothers get infested a week ago, used a very strong 1-5 ratio of H202 and water. Sprayed the soil, shit was making the dirt bubble, i made sure to get a good coverage. no gnats sense. i understand it killed my living soil, but that can be fixed and to boot i saw amazing growth the week after.
 

del66666

Well-Known Member
wait I thought he said to water the soil with it to kill the larvae. What is the spray for?
you need to dilute the neem in water by using a few drops of liquid soap to make emolient before using on plant.the neem mix can be sprayed on leaves and soil only at lights off, it is safe to use. or hang a few chemical fly strips up at lights off to kill adults
 

quietguy420

Well-Known Member
Save your self a headache, the neem is a joke when it comes to the larva, you have to use so much that it virtually kills the plant. And it only slightly deters the adults from laying more eggs in the soil. Go get a 5$ bag of Diotamacious Earth from walmart or lowes and put a thin layer over the top of soil. Bottom water for a few days and viola. Ez Pz.
 

reh420

Member
1-5 dilution of 3% h202 to water, shit will be dead within hours. Not to mention it will kill off some of the left over organic material in the soil thats attracting the gnats and larva in the first place. Oh and if adults land to lay more eggs, they wont make it far, try getting it on your skin.
 

del66666

Well-Known Member
Um,...Could you explain the problem with those hours? I'm sorta confused. *scratches head*
cause i said use neem at lights off... scrap the neem, you need lights off for 12 hours in my opinion, sand on top, fly killers hung up in small grow cabs is good or any of these others sounds fine, save the neem for spider mites which ive got if you would like some..
 
The size of the room is about 18' deep and 3' wide its a closet. The hours issue is they are on a timer and only go off when I'm not home will changing the light schedule on autos cause me major problems. Also if I follow one of these solution guides should I be feeding these plants to help strengthen them up?
 

reh420

Member
Probably wont do any harm if you feed them using chem nutes, but organic nutes would most likely exacerbate the problem.
 

jawbrodt

Well-Known Member
cause i said use neem at lights off... scrap the neem, you need lights off for 12 hours in my opinion, sand on top, fly killers hung up in small grow cabs is good or any of these others sounds fine, save the neem for spider mites which ive got if you would like some..

Ahhh, gotcha. Yeah, I agree with scrapping the neem(I.E. 'gourmet fungus gnat food'lol), going with sand and fly strips. I used them with great success, eliminating those little bastards within two weeks. Also, I don't remember what medium you're using, but, if it's MG soil, throw it in the compost pile, or you'll have gnat problems forever. They come pre-packed, as some kind of sick, twisted, bonus. :lol:
 
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