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Get Rid of Fungus Gnats For Good Using Mosquito Dunks

moses wellfleet

Well-known member
Moderator
Veteran
I am giving Vectobac as a soil drench, BTi is the active ingredient. All advice says to let the soil dry out because the gnats love moist mediums. Surely the BTi will be less effective if the soil dries out? Should I just keep drenching the soil with the Vectobac? Decisions decisions

Anybody else been down this road before and know which fork I should take?
 

Muleskinner

Active member
Veteran
"letting the soil dry out" is a relative term. You don't want it to get dry enough to stress the plant. I've noticed no improvement in gnats with the soil getting dryer, they seem to thrive no mattter what.

I think the Gnatrol (Vectobac) is only effective in the soil for 48 hours, I wouldn't wait more than 3 days to water if you have a heavy infestation. If your soil is still very wet after 3 days you probably need more perlite and less compost in your mix.
 

moses wellfleet

Well-known member
Moderator
Veteran
"letting the soil dry out" is a relative term. You don't want it to get dry enough to stress the plant. I've noticed no improvement in gnats with the soil getting dryer, they seem to thrive no mattter what.

I think the Gnatrol (Vectobac) is only effective in the soil for 48 hours, I wouldn't wait more than 3 days to water if you have a heavy infestation. If your soil is still very wet after 3 days you probably need more perlite and less compost in your mix.

Hey thanx friend. Yes my common sense is telling me to rather water it in than try wait it out with dry soil!
 

Loc Dog

Hobbies include "drinkin', smokin' weed, and all k
Veteran
It does not make sense to let it dry out, since it is bacteria. It is meant to be put into ponds to kill mosquito larvae.

I stock piled RO water in my office, and threw in mosquito dunks, like you can get at home depot, and let hem float in it for a few days before mixing with nutes and watering coco. Doing that I finally got rid of them completely. Also yellow sticky traps will get any stragglers.

I had them like a plague, when first started using coco. Would be breathing them in. I heard people say the come in bricks of dry coco, but not sure. This is from wikipedia -

Fungus gnats are typically harmless to healthy plants - and humans - but can inflict extensive damage to seedlings; their presence can indicate more serious problems. In houseplants, the presence of fungus gnats may indicate overwatering; they may be feeding on roots that have been immersed in water too long and are thus rotting, or the gnats may be attracted to fungus growing in saturated topsoil. Consequently, allowing the soil to dry may reduce their numbers.[7] The pests are sometimes also managed by placing a layer of sand[8][9]or indoor mulch on top of the soil around plants; by introducing Hypoaspis miles mites or applying the biological larvicide Bacillus thuringiensis (var. israelensis) to kill gnat larvae; by drenching the soil annually in an insecticidal soap; or by applying detergents and nicotine from tobacco brewed into a toxic tea.[citation needed] Hydrogen peroxide can be mixed with water and used to kill fungus gnats.[4][1]
Since the gnats are weak fliers, fan-based traps as well as other fly-killing devices may be used to help control free-flying gnats, especially indoors. There are a number of toxic and non-toxic methods of controlling fungus gnats and their larvae, including nematodes, diatomaceous earth, or powdered cinnamon.
 

Ghostin

Active member
Hey world,

Just wanted to share my results with Mosquito Dunks. Crumble them on top of your soil or coco (enough powder or crumbs to lightly coat the soil ~ .5-2tsp each depending on size), water, and let them work their magic. They really work to effectively rid you of fungus gnats (or mosquitoes, lol) in about a week or so. Preventative care is better than active madness so be sure to top your fresh/new soil with MDs. Haven't had gnats since I started using them!
 

DocTim420

The Doctor is OUT and has moved on...
Try Mosquito Bits instead of Dunks. Cheaper, easier to apply (no crumbling) and they release BTi for about a week or two.
 

DocTim420

The Doctor is OUT and has moved on...
Bits are granulated corncob bits with BTi applied via vegetable oil. Amazon has the best deals...imo. BTW, technically, Bits are not "organic approved" (due to vegetable oil application)--whereas the Dunks are.

I use Bits at the rate of 5 ml/gallon in water and mix 7.5 ml into the soil surface of plants in 5 gallon containers about once a month or so.
 

Muleskinner

Active member
Veteran
Preventative care is better than active madness so be sure to top your fresh/new soil with MDs. Haven't had gnats since I started using them!

totally agree, you have to use the BTi when you transplant to knock them down right away. If you go untreated for a week or two the population expodes and then it takes longer for the Bti to work.
 

Ghostin

Active member
Thanks Doc!

Yah mule, they sneak up on you with the quickness. At first you think "maybe I spilled some soil on the floor" but then you look closer and it's hundreds of dead insect bodies! Fuckers..
 

DocTim420

The Doctor is OUT and has moved on...
Ghost--and YELLOW CARDS!

I buy mine on Amazon and clip one to each container. That way, it is easy to identify a "hot plant". IMO, infestation does not instantaneously happen to all the plants at once--rather the little shits migrate from one plant to another. If I can identify and treat the "hot plant" early (the one with the most black dots on the yellow card) then I know in about 14-21 days I will not have another wave of FGs....or at least not as big as what it would have been.

Saponins too...been playing around with strategic yucca saponin treatments and it seems to help. Kinda new idea...

Google: "saponin" "pesticide"
 

Smoggy

Member
Zapp Em!

Zapp Em!

Haven't had em for years in rockwool, hydroton/coco setting;
but just brought in an apparent virulent strain w/ new plants.
Import plants had even been treated w/ Thurgicide liq. & beneficial nematodes a week prior!

Just noticed toast ones inside 1K MH light fixture- theyve been multiplying steadily!

So gonna employ old [ Non- Toxic] multi-pronged strategy:
ReDose all ($eedlings and clones are most susceptible) w/ a Fresh batch of nematodes & Gnatrol granules.
Plus a couple novel devices, i believe made a decisive difference before & haven't heard anyone else reccomend:
Electronic Mosquito zappers!
A tight-grid small unit, hooded to reduce glare, placed under table on nighttime timer, was the set up.
Unfortunately, my prefered Flowtron bk-7 been discontinued for over a decade- apparently a lemon-design. They burnout bulbs prematuely & inner zapper cage plastic breaks down from UVs! :lightning:
Like mosquitos these gnats are attracted to light and CO2 from the root exhalation, but since much smaller can fly thru big grid yard zappers.
A first gen. Stinger UV vacuum fan model tried had weak pull & only lasted till ~year after warranty motor died & had to add finer screen to catch compartment.
A plug-in nightlight Flea Trap also works good. Enforcer's overpriced and flimsy, but McGuyverable w/ a green Christmas bulb in night light & sticky mouse trap cards from 99c!
Gonna also build one those U-tube sodabottle yeast CO2 mosquito traps' see what i catch:
Get em'
:tiphat:
 

Smoggy

Member
Correction:
Just confirmed it was Microbe-Lift product used initially [Much more than instructed!] , not Thurgicide brand.
 

mdgg4

Active member
just threw a bunch of cuts and plants out because of gnats, fuck those bastards! tried EVERYTHING to get rid of the fucks but those bitches are resillient as fuck. they will be back dont care what you use, gnatrol, bti, that shit not gonna knock them out if thats what your looking for. i got tired of them and spending shit loads of money on this and that promising to get rid of them. what i personally see is they reproduce too fast for bti to be effective on its own. ive literaly watched dying gnats still try to get their fuck on, dying! they are so preprogrammed to reproduce that thats all the adults know. the plants i ended up keeping still has gnats, they will always be there unless i treat with something that i know i dont want in my garden since i been on this organic shit. so what i did was saturate the pot with a powdered bti product purchased from arbico organics. i then took all pots and placed them inside of some $20 all mesh bubble bags purchased from amazon pack of 8. bought several sets. in my humble opinion this method to me is sure fire nothing can get in or out and pots still receive air, win. i also purchased a product called "mantis" which i highly recommend especially if your battling mites. but i use every where spray under and around every where after youve cleaned and bleached every fucking thing in your garden. plan is to give them nowhere to go and no food to eat. the mantis will knock them flat on their asses with about a 3 hour kill window, and it smells fantastic all organic, the usual oils but i guess they found a winning combination cause it works. its about $60 for 32oz bottle, worth it. but anyways thats my take on gnats do not underestimate them, i just lost some prize plants due to them, they will fuck your roots over, the babies, those are the destroyers, the fucking babies! but im on a rant now gnats have caused me major damage and had to run off.


PEACE!
 

mdgg4

Active member
correct! bacillus israelis thuringiensis sticky traps etc..

maybe spinosad...

tried AALLL that, none killed them all, running alone or in combination, slowed, yes, erradicate, no. goal is to get rid of them, contain your pots, then treat better success on plant going full round, when done you can remove entire pot from room with gnats contained, then burn, just kidding, but you just removed gnats, larvae and eggs from your garden,easy.

PEACE!
 
I say use Diatomaceous Earth..... put a heavy dusting on your top soil, it will kill off knats, the DE cuts thier bodys, i use DE and mosquitoes bits, same company making mosquitoes dunks its a granduler form you can spread out on the top soil. Its toxic to the lil bastards. im knat free with this combo
 

mdgg4

Active member
de will do nothing against gnats, gets wet no good. also takes too long to kill the adults 24-48hrs. they will still mate during this time and possibly still lay eggs while dying from de. plus attacking the adults will actually not do anything the larvae is what you need to control. save the de de for the pests running around on the floor, will do shit against gnats. personally i dont recommend against them. DE WILL DO NOTHING AGAINST GNATS

PEACE!
 

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