Fungus Gnats

[Proud Marine Dad]

I think most of the problems I have had with my potted plants this season has been partly due to the fact that I have fungus gnats in most everything.
I am now wondering if the potting soil I bought is the culprit.
I didn't see any gnats when I potted them but that doesn't mean the larvae wasn't there in the soil.

I have sprayed 3% hydrogen peroxide onto the soil, and neem oil onto the soil with little results.
I decided to try hot pepper sauce mixed with water so I put a bunch of Sriracha sauce into some water and hosed the soil with it.

I guess if this doesn't work I am going to have to get some BT (israelensis) or Pythrethrum and spray with that.

 

[rabid48]

Buy mosquito dunks, put one in your watering can, water your plants, problem solved.

You'll probably still have to squish a few of the flying ones though.

 

[Cayennemist]

Will BT kill mycorrhizae?
I have been trying to avoid using all pestasides, organic or not. I am having some sucsess maintaining a biofilm on the leaves. However, I still get F gnats
in my soil. If my plants were outside I wouldnt care, but they are in a greenhouse, and that just means shelter for them. The one thing I am concerned with is killing the myco's that I have been trying so hard to colinate. BT (Bacillus thuringiensis) the main ingrediant in mosquto dunks, is a microbial insect killer.

The same bacteria is good for killing catapillars awsell. So the 100$ question is: "Will it effect my mycorrhizae."

 

[nee]

I have sprayed 3% hydrogen peroxide onto the soil...

Aren't you meant to actually water with it though, as opposed to just spraying?
The larvae can go pretty deep and i'm guessing that just spraying the top won't get them.
I've yet to tackle my fungus gnat problem..they are a pain!

 

[Pepper-Guru]

Make a fungus gnat trap. Use peppers as bait....done. Works for me. Take a plstic coke bottle, cut top off, invert and insert into remaining bottle body. Like a funnel into the bottle. Tape edge to seal and stick some pepper pods into the trap. You will catch them ll. They fly in but not out.

 

[Proud Marine Dad]

Make a fungus gnat trap. Use peppers as bait....done. Works for me. Take a plstic coke bottle, cut top off, invert and insert into remaining bottle body. Like a funnel into the bottle. Tape edge to seal and stick some pepper pods into the trap. You will catch them ll. They fly in but not out.

I tried this Rich with white wine vinegar as a website I found said to use vinegar. Left it overnight and not one gnat was in it.

I have sprayed 3% hydrogen peroxide onto the soil...

Aren't you meant to actually water with it though, as opposed to just spraying?
The larvae can go pretty deep and i'm guessing that just spraying the top won't get them.
I've yet to tackle my fungus gnat problem..they are a pain!

The site I read it from said to "spray your plants" so I assumed they meant spraying with a spray bottle.
I too thought maybe watering with it would work better.
I am going to get the mosquito dunk as was mentioned as I have read a couple of sites that said to do just that.
I forgot what's in the dunk though. Is it BT? I think so and probably the one I mentioned above the israelensis strain.

Mosquito dunks and sticky strips tomorrow.

 

[Pepper-Guru]

Vinegar? Use peppers and I promise it will work.

 

[Proud Marine Dad]

Vinegar? Use peppers and I promise it will work.

They said vinegar because it is decaying matter and would attract them. Made sense to me.

What kind of pepper? Like fresh ones from the store? I only have some yellow wax peppers in a jar at the moment.

 

[Pepper-Guru]

No like the ones that come off your plants they are flying around. Chinense work best. When they go in, slosh around the stuff to kill em and set back where it was.

 

[Cayennemist]

Corn, Coffee, Banana, berries, apples, are also good attractants. I leave cups of coffee around with a little success.

Im going to try a hybrid of what Guru said and this. Ill make a bottle with coffee and fruit in it (I have no peppers atm)

 

[Proud Marine Dad]

No like the ones that come off your plants they are flying around. Chinense work best. When they go in, slosh around the stuff to kill em and set back where it was.

None of the plants have fruit yet.

Corn, Coffee, Banana, berries, apples, are also good attractants. I leave cups of coffee around with a little success.

I have heard that a slice of potato will attract them as well.

 

[Cayennemist]

No like the ones that come off your plants they are flying around. Chinense work best. When they go in, slosh around the stuff to kill em and set back where it was.

None of the plants have fruit yet.

Corn, Coffee, Banana, berries, apples, are also good attractants. I leave cups of coffee around with a little success.

I have heard that a slice of potato will attract them as well.

Come to think about it, those bastards infested a sack of taters I had in my pantry a few months ago


OK HERE IS MY PLAN!


1. Bottle like guru said

2. USE what I have as bait

3. Add coffee as it will help kill the little bastards

 

[Pepper-Guru]

Nice illustration!

 

[Cayennemist]

I know... I should get paid for this!

 

[corene1]

I too had a bad gnat infestation. With a lot of help from the people here and some research I have it under control. I used a 4 to 1 mix of h2o2 and water and poured it directly on the stem and down through the roots. I then got a 25 gallon container and used it for a watering source , always keeping a mosquito dunk in it . I also got a bottle of SNS 203 from the local hydroponics shop and use it in my watering every couple of weeks . it is a systemic repellent that absorbes through the root system making the root toxic to the larvae. As far as killing the mycorhhizae, I don't know . I did introduce mychorrizae back into the potting soil after the gnats were under control and the plants are looking and growing very well. I just transplanted 70 plants to their final containers and did not find a single larvae in the root ball.

 

[Lawrence]

Just a thought, how about getting a sundew plant, no chemicals or mess and the plant makes its own bait!
Plus it is so satisfying to see the bugs stuck to it.

 

[Proud Marine Dad]

OK HERE IS MY PLAN!


1. Bottle like guru said

2. USE what I have as bait

3. Add coffee as it will help kill the little bastards

They are attracted to yellow objects so sticky traps would do the same thing I would think.
I may just get a yellow piece of paper and spray it with 3M Super 77 adhesive. It may do the same thing for free.

 

[nee]

The site I read it from said to "spray your plants" so I assumed they meant spraying with a spray bottle.

Ah ok...did you do a search on this site though? I have looked into this a lot lately, as i need to sort my bugs out too!..and all of the topics i've come across on THP say to water thoroughly with the stuff, which kills the larvae....

 

[Pepper-Guru]

Any time I've had them flying around the house it was almost always due to peppers I had laying around. That's what made me use them as bait. I do like that plant idea though! Good one!

 

[Cayennemist]

I use Sticky fly strips, but I am afraid to get them too close to the soil and have the leaves get stuck on it. And who wants those things hanging around where you work.
I have had them stick to my arm hair, forehead, shoulders, etc.

I heard about the sundew as well, but I wonder how hard they are to grow? Has anyone here tried one?