Fungus gnats

I have been doing some research on riu to figure out why i have a few yellowing leaves. Then i found out that fungus gnats can cause what appears to be nutrient deficiency. i have been seeing 1 or 2 every time i water. i put up fly ribbon to solve the problem. before researching i thought that was all i needed to do. i am thinking about using neem oil since lowes near my house sells it. i have been wondering about using sand to kill larva. i read on a thread that a foam plate cut to size so that the soil is covered will work like sand. i do not see how this is possible so if anyone can help explain that would be nice. so i guess i will get to my questions.

How much neem oil do i need to use and how often? do i just follow the directions on package?

how deep should the playground sand be and should i use some type screen to make it easier to remove before my next watering? also, if anyone has any better ways or removing the sand let me know.

i have also read that using black aquarium rocks. can work in place of sand?

I do not know if it is important but here is my set up.
-soil mix is: 60% scotts topsoil, 25% perlite, 10% vermiculite, and 5% worm casting, blood, and blood meal.
-currently using 2-100w cfls per plant.
-i am just over 3 weeks since seeds broke the surface.
-i water about every 3 days depending on weight or pots.

The neem oil won't work. Actually, I think the little bastards eat the stuff. I had a really bad problem with them before, I used sand and it worked great. All you need is enough to make a thin layer on top of the soil, then wait a week or two and they'll be gone(except maybe one here and there). The plate idea might work too, as it would block the adults from laying their eggs on top of the soil, and they would die off just the same as if you used sand(in theory.lol). Anyway...I think you're problem is something else other than the gnats, because my infestation was really bad, and I never had any deficiency problems or plants damage from them.(it takes alot of them) So, I'd recommend looking into other solutions while you're taking care of the gnats, because I'm pretty sure you also have some kind of nute problem too.

If you see them fling around, you got a problem. I had the same thing going on. Oh what can a couple gnats do. They will fuck your shit up. Use an Azamax drench and they will die.

Little bastards are always present here. If there aren't that many they don't seem to bother the plants, though id rather them be gone completely. Using peroxide enriched water kill the larva guys? SEEMS too in my case but what do I know. Having a fan blowing on the soil might help. Would think it would make it a b*** for them to lay eggs down in the soil if they cant get too it lol.

-best wishes

They will get into the drainage holes at the bottom of your pots and lay eggs down there too. I've had them and they've never caused me any problems. The larvae live down in the soil and feed on the roots and other organic matter. The adults don't eat so they don't cause any problems. I suppose if you had a whole bunch of them they could cause some issues.

there is also a product out there called GNATOFF it has bacterium in it that stops the larvae from feeding. i got some of these in some cheese clones i got given..

2 applications and problem solved but then i only found 4 flyers total i took 5 clones.

^Nah, you can leave the sand right there, it won't hurt a thing. Actually, some soils have sand added on purpose, for drainage and compaction issues.

P.S. If the only drain hole you have is the one on the center of the bottom of the pot, you shouldn't have to worry about flies getting to it. They normally get into the holes on the sides of most pots, so i don't think they'd crawl underneath to get to your's.

KILL
THOSE
ASSHOLES

They have been fucking my shit up for a week now. I transplanted and I could actually see how much root mass they ate!!!!!

Home Depot has a specific can for them $7 Nice tip on the sand

logzz said:

KILL
THOSE
ASSHOLES

They have been fucking my shit up for a week now. I transplanted and I could actually see how much root mass they ate!!!!!

Home Depot has a specific can for them $7 Nice tip on the sand

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I feel your pain good luck.

what is that item called for 7 dollars, and is it natural?

do you think my local garden store would have anything for them?

i am going to to try the sand before i go to anything more extreme. i will post my results.

also if anyone has any other ideas or information let me know.

thanks everybody i luv this site.

^Seriously, the sand works great. I had tons of those little bastards, and it took care of them completely. Now, I'm lucky if I see one a week. I did have a problem with the sand though. I used colored playbox sand(they were out of non-colored.lol), and when i covered the top of the soil,(about 1/4" deep) I couldn't water them because it wouldn't soak through the sand. Weird, huh? Who the hell would think that water wouldn't drain through sand?LOL I'm not sure if they added something to the sand that would make it do that, or what, but i swear that the water would sit there on top of the soil, even if i left it there for an hour. So, I ended up scooping most of it off, leaving a light coating. It still slowed the watering, so i had to stir the very top 1/4" of the soil(I used a large nail.lol) sometimes so they would get watered evenly. Otherwise, the water would run through a few areas of the soil, leaving other areas dry.

I'm the only one I've heard that ran into that problem, so i'm guessing that the colored soil had some kind of safety additive or something that caused the problem. IDK, I'd like to hear from others who used sand, too, and see if they had any problems with it.

Anyway...it still works great. I started using an old garlic powder container to sprinkle a nice thin layer, and didn't have that problem anymore. Plus, the flies are gone.

No it is not natural unfortunately but it had to be done. It was called "spectracide- Triazicide" Im going to try the sand but when I transplanted I noticed the main problem was in the root ball.

I do not get paid until the friday. i do not even have money for gas. i spent too much money last weekend upgrading my set up. so to stop those bastards until friday i cut some card board to recreate what i saw done using a paper plate. it is completely covered and i used rocks at the edges to weigh them down. so it will have to works until friday. we'll see.

i used to just have an expensive habit. now until i see results i have both an expensive hobby and habit.

i used to just have an expensive habit. now until i see results i have both an expensive hobby and habit.

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Once you get things running smooth, you'll be glad you spent the time and money on it. I eat the stuff for a sleep disorder, and it was getting quite expensive. Now that i grow my own I don't have to buy it anymore, and although it cost quite a bit to get everything setup right, it's well worth it now. It get's pretty expensive buying a 1/4 oz every other day.LOL

the cardboard did not work out well. they were getting through gaps where i had to cut for the stem. this may sound weird, but i had a big roll of duct tape. i layered it to create a seal they are not getting in. i have about 2 days till i really need to water. after i water i will be putting down some sand. it appears to be working great i have not seen any flying around since i put the tape on. hopefully i never see one of those bastards again.

the tape was a stupid idea. all it seemed to do was hold in moister. i now have sand down. it has been about 5 days and i have not seen any gnats since. if any one is researching for a solution for their gnat problem here it is SAND. thanks everyone

If u dont kill them all they will never leave. Yes they dont do much to a plant a couple weeks from harvest but left unchecked they WILL get into your clones and seedlings and kill them quick. No if ands or buts about it. I know first hand.

Alrighty then, Sounds to me like i need to go get some sand, just gave massive does of Neem Oil per My Books recomendation and now i read that the little buggers eat the shit....lol....

SAND! I had a slight problem with them and the sand worked great for me too. I feel like since it dries so fast the adults won't lay their eggs their and no eggs means no more adults. I haven't had a single one since I put down the sand. But I would recommend removing the top 1/4 - 1/2" of soil gently with a spoon. I'm not sure if anyone else as said that, but that's what I found works well.