Fungus gnats!!!!

Has any ever had a fungus gnat problem? How did you get rid of it. I don’t want them to infest my seedlings.
So far I only see a few of them around and I got some yellow sticky pads and pyrethrin concentrate and did a very diluted spray for the first time today since my plants are so young. Any suggestions?

What type of pots do you have them in? If they are in plastic pots that have holes in the bottom, then you need to cover those holes with something that is breathable but still won't let gnats get into the holes to eat your seedlings roots and lay their eggs. Then you need to lay at least a 1/4 inch layer of diatomaceous earth over the top soil of your pots. I use a piece of Frost King ac filter to protect the lower pot access holes....

If you have pots that have bottom holes like this....



You can use something like Frost King AC filter to cover those holes...



An example of a pots lower holes now protected from gnats...

You want some BTI. It's a bioliogical pesticide that will take care of them and mosquitos. You first need to catch some on a yellow sticky trap and make sure they are not winged root aphids. They will require different treatment. Gnatrol and mosquito dunks are both forms of BTI.

Micro-Lift BMC is the most cost effective BTI I have seen

Yep, like Renfro said, you can't beat Microbe-Lift, its one of those things any serious grower should always have on hand!

So what I have is no good?

Gnatrol.com dude sends it by the qp Contains BTI

What you have should be fine. I recommend throwing in the 1/4 inch of diatomaceous earth as someone else mentioned to climate the problem but you shouldn't see any large outbreaks using those 2 things. It's harder in flower when you should avoid spraying them but if you can get a bunch of the sticky papers in each pot that should control the situation. You'll be fine.

The sticky traps you posted are meant to hang on branches, you need the ones that can be stuck into the soil to catch the babies before they start flying and making eggs. Diatomatious earth prevents the eggs from reaching the soil so they don't hatch, a combo of the 2 worked great for me.

Also if it says keep out of reach of children it's definitely not something you want to smoke. Like I said, good for veg but avoid in flower.

Blend neem seed meal in with your grow soil or coco. Neem seed meal is good for plants but kills soil bugs. That's for on ur next run, don't dig up and blend now.

Sprinkle DE on top of soil and water in SF nematodes. They kill the gnats and lots of other pests. They are parasites that are small, they infest the host bug and kill it.

$12.99...
https://www.amazon.com/Million-Live-Beneficial-Nematodes-Exterminator/dp/B00I0ZUGLK/

Beneficial nematodes for the eggs and DE for adults

Yeah, DE, like already said.....its available everywhere, cheap bed bug killer bottle @ hardware store/ pharmacy, etc, whatever. Just dust the topsoil/floor and sit back, repeat till happy ; )

I make cheap traps if they come around m, A bowl or some empty washed out tuna cans. Add Water, some apple cider vinegar, and a few drops of dish soap.

many good tips given here.

fought them several times.

What helped me are:
yellow sticky tapes
fruit fly traps (works for gnats and flys, the water atract them)
nematodes
BTI
Pyrethrin based products help also, used fly spray from the supermarket (use with care, and just in veg!, contains some petroleum)

all these methods can be combined, pyrethrin dont hurt meatodes much.
DE hurts nematodes.

I used Mineral Magic as top dressing, similar to DE guess, it helps, but hard to keep the surface covered.

What dont worked was:
H2O2 peroxide drench

Combine some methods to get rid of them and get all stages, sticky traps near the surface of the pots, bti and nematodes.
Apply every few days some BTI for 2 weeks.

Nematodes dont attack the egs, but the larvae in all its stages.
BTI the young larvae on contact.
The yellows catch some adults, or knock them down with some spray.

Nematodes can be mailordered and are quite effective, more then the BTI as they act active, BTI is just passive but have the advantage that you can store it.

In the meantime give some pyretrin and use the yellows.
You probably can kill them allready with what you have, but more is better in this case.
They come easily back, 10-14 days is a reproduction cycle.
When you see some, be sure they return latest 14 days later as long you didnt kill them in their larvae stadium in between.

neem oil will kill them too

Yellow stickies for the adult flyers and 3 drenches with Gnatrol for the larvae. Works every time.

tellin ya,

Cinnamon, 2 teaspoons per 1 gallon of media, you will NEVER see a gnat again in your grow room.

Premix into your media before seed/transplanting

I had them always till i did this, and havent seen a single gnat since.

InTheValley said:

tellin ya,

Cinnamon, 2 teaspoons per 1 gallon of media, you will NEVER see a gnat again in your grow room.

Premix into your media before seed/transplanting

I had them always till i did this, and havent seen a single gnat since.

Click to expand...

Thats the best organic trick for larvae killing... Cinnamon will kill shrooms that fungus gnats larvae eating
and then you just need those yellow sticky traps to catch flyers..

am was have so huge infestation but Cinnamon Challenge for Gnats is best thing,most fastest action
and total destroying hole infestation..

Sticky traps, if you can put a fan on the floor blowing over the pots. These two combined will take care of it without pesticides.