fungus gnats! tried nearly everything in the course of a year.....

Well, I've got a fungus gnat problem. It's a very small problem now, I only notice a bug every day or two, but they have not left for over a year now! I've tried all the different methods and many different sprays organic and not, nothing seems to work. I then proceeded to gut and clean my whole grow room ceiling to floor (this was in between my grows, when I had no plants and no possible way for them to be in any kind of soil) I kept the room completely empty and clean for about 3 months, and they are back again! I have no idea what to do, I'm thinking I might have to locate to another room.... Can anyone help? I can keep the gnats to a low population and somewhat under control, but I cant get rid of them!!!!

have you tried beneficial nemetodes. Ive seen people use them to control gnats

gnats are caused by overwatering. gnats thrive from constant moist soil. That is your problem. 2 things can really help. Are you using ffocean forest soil? helps greatly with drainage. water only when they need watering by picking up the pot to feel the weight. notice how they weight when just watered and when ready to water is the trick. I say stop watering for 4 to 6 days for a while. the plants like to dry a little before watering.

want to stop em immediately....put some sand (not much just enough to cover em maybe 1/8 th inch. get the bagged playsand from homedepot. that is short term. I don't like the idea of sand perm in my pots. causes them to weight a lot more and hard to tell when i pick em up if they need watering.

keep em under control....get neem oil and add some one time a month....if they your growing correctly you wont need it for long....

neem oil keeps them from reproducing. doesn't kill em off though. Its natural..and smells bad imo.

Relaxed said:

gnats are caused by overwatering. gnats thrive from constant moist soil. That is your problem. 2 things can really help. Are you using ffocean forest soil? helps greatly with drainage. water only when they need watering by picking up the pot to feel the weight. notice how they weight when just watered and when ready to water is the trick. I say stop watering for 4 to 6 days for a while. the plants like to dry a little before watering.

want to stop em immediately....put some sand (not much just enough to cover em maybe 1/8 th inch. get the bagged playsand from homedepot. that is short term. I don't like the idea of sand perm in my pots. causes them to weight a lot more and hard to tell when i pick em up if they need watering.

keep em under control....get neem oil and add some one time a month....if they your growing correctly you wont need it for long....

Click to expand...

Heres the thing, I didn't have anything growing in my grow room for the last 3 months and my current plants are only 15 days old at this point. I use FF Ocean mixed with a tad more perlite so the drainage is great, and I am sure I am not over-watering at all, if anything, slightly under-watering. I mist about 3 times a day to keep any bugs off the leaves, and leave bowls of that fungicide spray highly deluded with water out and that helps some. I haven't tried the nematodes though...

Also I have water / ph monitors for the soil to tell if they are too moist or wet and pH. I'm not new to growing, I just can't shake these gnats!

this is all you need
its a paper plate
cut to size and remove to water

Does that prevent aeration to the roots at all? And what about the holes on the bottom/side of the pot lol? I've seen them get in there before... But I will give it a shot, nothing else is working

Most of the water meter soil testers may not work well? Go with the pick up pot approach. Your doing something to allow them to thrive. Couple weeks of plants in constant too moist soil can and will produce knat issues. I think you did well by cleaning out the place. Now try the less is more approach. Get some sand for the top coat to ride the knats now. Neem oil additions to the soil 1 per month should get you on the right track. Stop spraying your plants for a while. Really check out the fact most dont spray plants at all.....only clones and maybe some clones as they trans to soil. Think you will find you have an issue over moisturing the plants so knats can thrive and reproduce. I had this issue as a youngster but I let em dry out going first for potted plants in 1, 2 and 3 gals. only watered 4 to 7 days apart. no issues now.

knats attack plants that are week, strained and unhealthy. They go away when all plants are healthy and green...

oh, use a knife or something and till/turnover your top inch or 2 of soil. That is where the knat live and lay eggs. This approach works when you don't go the sand top coat route. They are feeding on your wet roots, not your leaves. They can keep plants unhealthy if not dealt with...will cause yield issues.

Yes and I do, this isnt an overwhelming problem like I've mentioned, I see one or two every few days at most but they wont leave. I'm afraid if I water less they will die because they are so young, but I will take that approach nonetheless. and thank you for all of your help, i really appreciate it!

ok good luck. Be patient, it will pay off. last thing...maybe the soil was left over unused soil from last grow? Maybe the soil stayed moist outside? Most hydro stores keep soil inside.

this alone will works great
but also do the water idea with this

what they dont tell you about the sand is it has to be removed before the next watering
but the cover will act as a light blocker
dont worry about the roots they will get plenty of O2 the cover is not glued on
its just sitting there

Relaxed said:

ok good luck. Be patient, it will pay off. last thing...maybe the soil was left over unused soil from last grow? Maybe the soil stayed moist outside? Most hydro stores keep soil inside.

Click to expand...

You know what, I usually buy my FF soil from my local hydro store who keeps it inside, but this time I got it from a local store who kept it outside. It's also older soil and went threw a freeze. I have a new bag I just wanted to kill that last one because it still had a good amount in it.

Have you tried loving the Fungus Gnats?

thats your problem. The soil stayed moist long enough to allow the knats to breed/lay eggs. You can reuse the soil just fine. Be sure to dry it out and flush if you didn't when growing with it.

When I had done my first grow I had experienced fungus gnats. I had 2 bugs flying around at the same time & killed them but then later on in the day I spotted another one. I went to home depot & got myself a hot shot no pest strip. After I killed off the last visible bug I have never had any more encounters with bugs. It's worth spending the 6-8dollars every 3 months to keep in your grow area.

The only time gnats show at my place is when I start playing around with Molasses. I can't tell they hurt anything. Can't we all just get along here? Leave the gnats alone.

BW

Well, man I hate to be the one to tell you this, but you probably don't have gnats... they're probably winged root aphids. Much worse! Check out this thread and take a closer look at these bugs:

http://www.icmag.com/ic/showthread.php?t=159960

These things are worse than spider mites so far IME. If you've tried mosquito dunks with no result then it's probably root aphids. It's worth looking into for sure because these bugs will diminish your yields and possbily cause worse problems.