Drenching a worm bin for gnats?

turnip brain

Active Member
I have a well established population of gnats in my worm bin. It is the beginning of growing season and I really have to eradicate these pests before they infest my grows. I have used dunks judiciously, added a heap of dry shredded paper on top as a barrier, and sprayed with spinosad repeatedly, but I only see slight reduction of the critters for short periods.

So, I am thinking first major step is to completely drench the bin with strong dunk and or neem oil solution.

If that doesn't do it, add neem meal/cake in the feed and possibly nematodes as well, but by then the cost starts getting out of hand.

So the question is: Will I kill worms with a serious flood? The bin has reasonably good drainage, but I anticipate it will be soaked for at least a few days before reaching moisture equilibrium again. I don't want to drown my worms
 

hyroot

Well-Known Member
Gnats are attracted to moisture. That won't help. Go buy some compost. Cover the top layer with a 1-2 inch layer. Gnats will be gone in less than a week. You can set a bowl of water off to the side to attract the gnats too. While the compost is working. They drown themselves flying into water.
 

turnip brain

Active Member
Gnats are attracted to moisture. That won't help. Go buy some compost. Cover the top layer with a 1-2 inch layer. Gnats will be gone in less than a week. You can set a bowl of water off to the side to attract the gnats too. While the compost is working. They drown themselves flying into water.
This is the most contradictory info I have ever heard about BT drench.

And, compost supports gnats. I do not see how this could possibly make a difference.

Luring adult gnats is one thing. Killing the larvae in the bin is another.
 

hyroot

Well-Known Member
Gnats like manure and guano, and lobster meal. They don't like compost. Layer a vegan compost and they will be gone. Guaranteed. Ask any organic grower. Works like a charm. there's different kinds of bt. The mosquito dunks don't work foe shit. You can add predatory mites too. They should already be there if your bin is attracting gnats
 

st0wandgrow

Well-Known Member
This is the most contradictory info I have ever heard about BT drench.

And, compost supports gnats. I do not see how this could possibly make a difference.

Luring adult gnats is one thing. Killing the larvae in the bin is another.
I combat them a few ways .....

If you are feeding fruit and veggie scraps to your worms, keep a ziplock baggie in the freezer and add your scraps to it. Fungus gnat (and fruit fly) eggs can hitch a ride in to your home in/on fruits and veggies, and freezing them will kill the eggs and help break down the scraps so that they are more easily processed by your worms.

I also tape a sticky trap to the lid of my worm bin to catch any adult gnats flying around. I also use a vacuum cleaner on occasion to suck up any adults that are hopping/flying around the bin. This is surprisingly effective.

I would also try drying out your bin a bit. Fungus gnat larvae need a moist environment (as do worms to a degree). I tend to keep my bin on the dryer side because of this. The moisture from my blended up fruits/veggies is sufficient. No additional water is added. I would also keep a nice thick, dry layer of bedding on top of the bin too.

Lastly, you can place a couple slices of potatoes on the surface of your bin. The fungus gnats are particularly attracted to this and will accumulate on the slices. Simply remove them after a day or two and replace with more.
 

turnip brain

Active Member
Already do these things:

-freeze all worm food prior to feeding
-keep a massive layer of dry shredded paper bedding on top.
-never add water
-I only wet the topmost surface of the top bedding with spinosad, not enough to get into the soil/castings.

I travel a lot, and day to day maintenance like adding and removing potatoes or vacuuming won't be consistent at all.

I think I will also add mozzie netting to the top over vent holes to prevent bugs from getting in and out. I suspect they can still crawl through the edges of the lid, but at least there will be a bit more deterrent. And though I hate spending more and more $$$, also looking into nematodes. Anyone use these? http://www.ladiesinred.com/store/index.php?app=ecom&ns=prodshow&ref=beneficial-nematodes
 

undercovergrow

Well-Known Member
Gnats are attracted to moisture. That won't help. Go buy some compost. Cover the top layer with a 1-2 inch layer. Gnats will be gone in less than a week. You can set a bowl of water off to the side to attract the gnats too. While the compost is working. They drown themselves flying into water.
this is true. i had a gnat problem with my worm bin too and i got it under control by not feeding the worms that week and making sure i had a good layer of coir on top of all food material. i also hung a sticky trap. i see one or two when i open the bin so i am definitely getting them under control. good luck!!
 

turnip brain

Active Member
Hmm, y'all got me thinking...

I already have compost, neem oil concentrate and spinosad so I am going to prepare some materials then layer on the following:

-A good feed

-A heavy top dressing of compost mix treated with strong neem oil drench (letting the drenched compost dry out to just moist before use

-Even more paper bedding likewise drenched with spinosad then dried to barely moist.

-Mozzie net the lid

Then leave for 2-3 weeks and see what happens.
 

Chano

New Member
A misting spray bottle with filled soapy water kills fungus gnats (and their larvae if you reach them). Also you can try to attract and kill them with a Vinegar Trap.
 

turnip brain

Active Member
Hmm, y'all got me thinking...

I already have compost, neem oil concentrate and spinosad so I am going to prepare some materials then layer on the following:

-A good feed

-A heavy top dressing of compost mix treated with strong neem oil drench (letting the drenched compost dry out to just moist before use

-Even more paper bedding likewise drenched with spinosad then dried to barely moist.

-Mozzie net the lid

Then leave for 2-3 weeks and see what happens.

Just a follow up, this seems to have worked. I got back from a trip yesterday and checked the bin last night and this morning and do not see a single flyer. And, the worms are vigorous/active. Looking good!
 

Hazydat620

Well-Known Member
From what I understand shredded paper on top, while good for the worms, won't help combat the gnats. Take some damp newspaper and lay the pages across the top of your compost. adding a lid to your bin will also help. You can also use corrugated cardboard, both of these acts as a barrier to keep the gnats out in the first place.
 

whitey78

Well-Known Member
Hmm, y'all got me thinking...

I already have compost, neem oil concentrate and spinosad so I am going to prepare some materials then layer on the following:

-A good feed

-A heavy top dressing of compost mix treated with strong neem oil drench (letting the drenched compost dry out to just moist before use

-Even more paper bedding likewise drenched with spinosad then dried to barely moist.

-Mozzie net the lid

Then leave for 2-3 weeks and see what happens.

I'm not quite a seasoned worm farmer yet but I've had one going on a year now and I am inclined to say that those bolded items above cant be good for the worms or the soil your adding the castings to eventually.... Do you get a lot of worms trying to escape out of top of the bin? If so this is a sign they arent happy with whats going on in the bin usually but I'm thinking you know that.

What kind of bin/setup are you using? I use these giant 27 gallon black totes with yellow tops in a manner similar to the green worm factory thing with the drain on the bottom... the one that has all the different levels where you fill a level with your desired composting items, insert worms... put another tray in that has holes in the bottom of it for the worms to get through; fill with bedding and feed, then its placed inside the bin that already contains my worms right on top of them. As they finish up the first/bottom tray, they migrate up to the next one with the new feed and so on...,,

The point I was trying to get across albeit not so well spoken or formatted; is that with a worm farm and (real) organic growing.... you are creating an environment that couldnt be any better for creating life in general as well as the containers; from the bacteria and fungi, all the way up to the worms... so its going to promote all the other life in between.... so a fruit fly or gnat isnt the worst thing to happen...

All that shit your adding cant be beneficial to the worms... I understand your treating the stuff and letting it dry (effectively reducing the strength of it which assists the bugs in building resistance) and all that, but its still getting to your worms, and eventually your soil... Your better off leaving things like spinosad or whatever else your adding (the oils specifically) out of your grow unless ABSOLUTELY necessary.

If your soil is on point with bug prevention (I.E. neem cake/meal, nematodes.... DE, and of course worm castings which naturally carry nematodes, protozoa and other things to help keep soil borne bugs and nasty shit in check), your grow room is clean, and you are freezing your refuse..... you should be in good shape... If they keep coming... Try to figure out the source... If your freezing your stuff prior and your still seeing a lot of gnats/fruit flies.... maybe they're coming from somewhere else, in which case you need to track down what and or where they're coming from and deal with them.....

I understand in the world of weed growing, likely starting where we all did with chemical ferts etc.... we dont like bugs.... at all.. I get it... I fuckin hate them too, but when you have a good organic eco system going on, a fruit fly and or a fungus gnat is going to pop up on occasion because life happens when the proper conditions are promoting it, however... as i stated above if your soil is prepared for these critters, they're going to leave it alone or be handled by it...

If you feel the gnats are a serious problem where they're getting stuck in your buds, because aside from their larvae growing in your root zone and the problems that go along with all that (if your soil is prepped..... this wont be happening), getting stuck in your bud is about the worst their gonna do....

The weather is getting nicer as of late so maybe you could setup a different location outside or something, or just outside your grow room if need be/possible. But I personally think you are over reacting with the neem oil and spinosad... sticky traps as a notification/monitoring device but other than that I wouldnt be putting any kind of oils or bug kill juice into your worm bin at all, its supposed to be natural and organic and what not, even though neem oil is basically organic, its not something I'd let touch your soil or anything thats going in your soil....

After adding that shit you may open up your worm bin and find that only the fungus gnats and fruit flies are alive...

Save all that for a real emergency because the more you apply spinosad, neem oil or the like without completely killing the population, your building up their resistance to whatever your trying to kill them with, and now you have it permanently in something you plan on adding to your soil...

I dont know how close you keep your worm bins in reference to your plants but I grow in 2 separate tents in one room, and the room next door is my "work room" where I keep my worm bins, my water source, soil.... etc... that room doesnt have a door on it so anything bugwise that pops up in either room is going to make it into the other room eventually... I mainly have bug issues when I have to bring in new soil into my grow, than I do with anything from my worm bin. Any and all bagged soil by roots organics, fox farms... anything other than straight coco coir thats "sterile" seems to come pre-charged with bugs right out of the bag so start thinking about a way to treat all your soil like I stated above with the nematodes and all that.

The only real way is to get your soil prepared and ready to kill anything that plans on laying eggs in your soil (A dusting of DE on your containers of soil/neem cake) and/or killing the eggs once laid (nemetodes and neem cake), as well as getting your soil properly ready to support healthy plants from beginning to end, along with a clean grow room and you'll have nothing to worry about even if you do see a gnat or fly here or there because its not gonna live much longer and wont be reproducing.

Good luck either way and let us know how you make out...
 

whitey78

Well-Known Member
Sorry.... My shits been kicked up a notch lately and it makes me obliviously a little slow.....moooo....

Obviously....

What's going on?
 
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