Hello again. Huge battle with gnats, many plants and have tried many solutions. I am into my 3rd week of using the mosquito dunks without noticing much difference. The dunks don't seem to dissolve, the solutions that kill on contact don't and could have bought plants with the money spent on yellow sticky traps. I know I started this by using potting soil that was outside at HD, and I shouldn't have used potting soil. I even torch the top soil and change some of the top soil. Drier soil doesn't work, they like that too. I am pretty new to this. I started in Sept. growing cuttings and have over 75 growing in my small basement. Could be an overdone thing too, but the wife's patience in wearing thin. Any help is appreciated, Mike.

  Mike, 
   
   Have you tried Pyrethrin?  It is a strong, natural insecticide derived from chrysanthemums.  Mix into a spray bottle and douse the soil.   http://www.ghorganics.com/PyrethrumInsecticideSpray.html

   If you have cats, ensure that the insecticide isn't permethrin.  This is the synthetic form of pyrethrin, and is toxic to felines. 

  Blue

gnatnix works

I am going through the same mess right now.  I know that they feed off of organic matter, and roots, and they really like wet soil.  Has anyone tried wood ashes on these suckers?  I know they will kill some insects, but I've never tried it on the gnats.

Gnats, those are killers. I Macgyver'd mine. Mixed red wine vinegar and dish soap in a plastic cup set it next to my plant and collected quite a few in a week

Mike I totally feel your pain. Between my cuttings and the two banana trees and one Meyer lemon tree I brought in to save from the cold, I have been fighting the good fight against those stinking fungus gnats as well. After months of using gnatrol, and letting the top 2 inches remain dry on the bigger trees, I am just now finally seeing an improvement as far as their numbers diminishing. I also started nuking all mediums prior to cupping my newly rooted cuttings and believe that has been a huge help in ensuring I don't bring new eggs in as I cup or up pot. Nothing seems to really just annihilate those little suckers though, and if you see one then ya know more may be along shortly. Thanks for the tip Blue, I am going to give that Pyrethrin a try myself! Some days I get so disgusted with those gnats I momentarily consider throwing all plants outdoors!

I'm a newbie, but here is how I saved some of my baby fig trees last year with BT spray. If you have no roots on your cuttings, it may be easier to just remove them from the soil, spray with BT, put them in a ziploc wrapped in a damp paper towel for a night, and repot them when you see no more gnats on your cuttings.

If you have lots of roots and need to save what is left, spray the soil with BT until saturated, repeat according to directions on bottle. This worked for me and I could see when it worked, since my cups were clear.

Lastly, prevent re-entry of future gnat hoardes with a layer of sand over top of soil and make sure they can't reach drainage holes either. This was a great tip another F4F member posted last year. So sorry, those gnats are a pain!

Gnatrol and yellow sticky traps are your friend. Also Pyrethrins and other insecticides that are not toxic to plants are an option as well.  I have even used pantyhose to help quarantine infected soil. In my limited experience a collaborative approach works best. Good luck, those little jerks are killers.

I have seen a gnat problem start a couple times. Both times I covered the soil with diatomaceous earth, reduced humidity, and they disappeared.  Gnats really seem to hate the diatomaceous earth.

http://www.gpnmag.com/fungus-gnats-and-diatomaceous-earth

Gnatrol and predatory nematodes, with the combination they will be 90% or more gone in 2 weeks(for me indoors in winter it was more like 99%, but I didn't have a ton of trees going like you do ). Pyrethrin is a knock down type control, it won't help with the larvae. Home Depot online usually has the best deal on predatory nematodes, make sure they don't freeze or cook in your mailbox before you get to them.
Mosquito dunks are a different strain of BT and don't work all that great. Gnatrol rocks, some people sell smaller quantities that they repackaged on eBay for a good price with little or no shipping charges.

I am going through the same mess right now.  I know that they feed off of organic matter, and roots, and they really like wet soil.  Has anyone tried wood ashes on these suckers?  I know they will kill some insects, but I've never tried it on the gnats.

Point some fans at the plants, gnats are weak flyers so they will avoid the area and it will make the plants stronger too. 

As several others have stated, I've had success with (food grade) diatomaceous earth. I just keep it in a glass bottle, with parmesan cheese type shaker top screwed on. After each watering, I just lightly powder the surface of the soil, and it really works. Also, if the powder gets wet, I do it again lightly after the soil dries out a bit because the DE works when dry. The gnats are no longer buzzing about.

Windowsill Garden also wrote that she used Hydrogen Peroxide, mixed 1 part to 4 parts water, if I remember her proportions right, when watering. Not only is this healthy for the plant and roots, but it also kills the gnat eggs.

Wishing you the best in getting rid of the pests, LJ

I had a big gnat problem with my 4 plants I am keeping in a plastic tote covered in plastic wrap.  They were getting out of the mini greenhouse and flying all over the office.  My wife was very unhappy.  I was spraying insecticidal soap with poor results.  I purchased nematodes and yellow traps.  The yellow traps arrived before the nematodes and they quickly, significantly reduced the gnats.  By the time the nematodes arrived, the problem was almost gone so I decided to wait before introducing more insects.  I was reminded of that Bugs Bunny cartoon where the home owner buys a cat to get rid of the mice, then dog to get rid of the cat, then lion... and so on.  So I skipped the nematodes and waited.  The yellow traps worked for me.  I used the product: "Springstar BioCare Gnat Stix S5333" and happy to report there are a lot of dead critters stuck to the traps, but not a single live one flying about.  I also see some dead guys stuck to the sides of the bin and wonder if the bleach I periodically add to the water in the bottom is making it toxic for the gnats?  Whichever, Gnats are gone: happy wife.  Fig plants are flourishing: happy me ;-)

Good Luck Mike 2 years ago I had a giant infestation of gnats they came from a bad batch of Miracle gro potting soil I used everything mentioned here and watched my cuttings die one after another finally I got so fed up I threw everything away This is why I use nothing but coco coir from here on out and of course you have to be careful what soil you pot the soil in after you start the roots in the coir I use pro mix and sterilize it in the oven and of course that kills some of the nutrients in the soil but that is easily fixed with some fertilizer take a look at this post I use paint strainers to keep the gnats from spreading if you happen to get them Good luck in your battle http://figs4funforum.websitetoolbox.com/post/the-war-against-gnats-7180106?trail=50&highlight=gnat

Dave,Andrew,Mike! nice bunch from Connecticut!

 Thanks for the help everyone. I have used everything but the pyrethrum and will try it also. I am marinating a garlic, cayenne & red pepper, dish soap & Dunk stuff, and will strain and test soon.

 Thanks, Mike

Hi,
You can reduce the number of flying gnats with the vacuum cleaner ( aspire them in). Just be careful to not harm the plants.
That works great with every flying insect.
Let the dirt dry a bit too.
You could try cinnamon sprinkled on the dirt once the dirt is dry.
Good luck !

Mario if we could find a couple more guys from CT we could have our own fig gathering ? 

Sounds interesting. I live in Wallingford, but work in Bridgeport. I have found at least 8 people with figs at work and a couple around town, (because I talk a lot) lol,. No one seems to know what they have, which makes it interesting. All I can tell is the two purples two people gave me are different by the leaves, and so are the two green ones. I am new to this, but there seems to be a lot of variety in the area, and figuring out the "locally grown" will be a hobby by itself.

            Mike

Guys -- no more fretting the fungus gnats. I had the worst problem with them in my house with 17 plants growing in the windows and I tried everything you can imagine...for years.  Finally found what worked for me and have NEVER had an issue since.  Its been over a year. Its called Neam Cake or AKA Neam Meal. Its completely safe, organic, and its actually very healthy for the plants as its a light fertilizer and root health support. Its much better than Neam oil for gnats because it stays at the top (as well as soil drench) eventually killing everything. Here's a video I did that explains everything:

A multi-prong approach has worked for me. I use sterile media (coir) for rooting, put a small square of yellow sticky paper in each pot, hang a sticky trap near a cluster of plants, use Gnatrol every time I water my indoor plants, and smash every one that I see flying around. I never seem to completely get rid of the buggers, but they also never grow to a significant population size. I might try add the wine vinegar and soap to my control measures as extra insurance.

This sounds like a good product. I like the fact that it's organic and actually feeds the plant while killing the gnats.

I use diatomaceous earth, along with a few other gnat-discouragers, but (although it's more a cosmetic issue) don't really care for the look or feel of the white powder over the soil. This neem cake blends right in, which is nice, but most importantly that it also has worked for you and others....Thanks for making and sharing the video.