Fungus gNats

hexthat

Well-Known Member
Fungus-Gnats.jpg
management and control
fortunately, fungus gnats are usually easily managed and can be kept in check in most orchid collections. Yellow sticky cards sold for monitoring and control of aphids and whiteflies are excellent for trapping fungus gnats. These cards are so effective when there are only a few flies that there is no need to use any insecticide on these flies. However, often female gnats will fly little so sometimes it is useful to cut strips of the cards and insert these strips into a pot to capture more of the females. Larvae are easily controlled by adjusting watering and ensuring that your orchid media is not overly decomposed and is draining well. This may require frequent repotting if you use a heavy watering regime.

The following points will help control fungus gnats:
1. Repot your plants on a regular basis and use mixes containing materials such as charcoal and coconut (fibre or
chunks) that are slow to decay, or inorganic components such as perlite;
2. Do not keep the media constantly wet and if possible allow the media to dry between waterings, especially the
upper inch or so of media.
3. Keep fertilizer to the minimum needed for the plant and adjusted to the potting media used.
Should these cultural methods not be effective or the collection be large, then alternative treatments may be warranted. However, the use of insecticidal drenches for controlling the maggots is not recommended, except as an absolutely last resort. Severe infestations of large collections may be best treated with biological control methods. The use of bacteria, nematodes, and predatory mites is highly effective in greenhouses and may work in large collections.
Bacterial treatment is most effective against the young larvae early in the cropping cycle and uses bacillus thuringiensis israelensis is sold under the trade name of gnatrol™ for greenhouse use. This type of b.t. affects only true flies (order: Diptera) and is different from the b.t. used for caterpillars in the garden. The b.t. causes paralysis of the maggots gut, stopping feeding and killing the maggot. Gnatrol™ is applied as a soil drench to thoroughly wet the soil of pots, flats, beneath benches, or other sites of infestation. It is only effective for about 48 hours so 2-3 applications may be needed with heavy infestations. Use of gnatrol™ is not recommended with simultaneous use of fertilizers or fungicides containing copper or chlorine. It will not affect the adult fungus gnats.
Parasitic nematodes are also useful for controlling fungus gnats. They enter the insect's body and multiply inside the host insect. While feeding they release a bacterium that is toxic to the host. The nematodes complete their life cycle within a few days so large numbers of infective stage nematodes are produced that will continue to search for new hosts. These beneficial nematodes can be applied as a drench to the growing media and to soil under the benches. Two common species available for greenhouse use are steinernema carpocapsae, sold as scanmask™, and steinernema feltiae, sold as nemasys™.
Finally, a small predatory mite, hypoaspsis miles also attacks fungus gnat larvae. These mites are usually sprinkled over or mixed into the potting media before planting. This mite is long-lived, will usually persist as a scavenger on dead insects while continuing to seek fungus gnat maggots, and will also feed on thrips pupae and other pests.
Chemical control of fungus gnats is diverse, but always a temporary remedy. Adults may be eliminated with any insecticide spray for flying insects, though this is decidedly a temporary fix and will not affect those adults emerging after the spray has settled. Good control of fungus gnats requires removal of the larvae, hence the high value of environmental management, i.e. Adjusting water schedules and repotting. Chemical control of larvae is best done with drenches of carbaryl, permethrin, imadichloprid, diazinon, malathion, and other common pesticides, and even isopropyl alcohol. However, and again, these are only temporary solutions as the flies will reinvade the pots once the chemical residue is degraded and the potting media remains wet and decaying.

I'm growing for my Girl Friend's mom, and Her son was taking care of her Mother plants (Lemon Larry OG and Purple Kush). When I got the keys to the grow room, I opened the door only to find Powder Mildew, Spider Mites, and Fungus Gnats. I have conquered Spider Mites and Powder Mildew, using Neem Oil and SM-90. I'm failing horrible at controlling the Fungus Gnats their numbers have doubled. I have put DE(Diatomaceous Earth) on the top layer of soil. I've noticed the females have been laying eggs in the drainage holes in at the bottom of the pots. Should I just let the soil dry up in between watering?
 

perkele

Well-Known Member
Hi dude, sorry to hear about your troubles. First thing...congrats on the war against the spider mites, never had problems with them (touch wood) and from what I read, they are a pain in the gardener's ars. From my previous experience, I had some problems with the gnats. Now...depends on multiple factors. Some will say having gnats it's a good sign cause that means your soil is very natural and fertile. Now...how old are the plants? The gnats, the adults, are not so dangerous, just nasty looking and annoying. Problem comes with the hundreds of eggs each female gnat is laying. The small larvae are the problem, and are a problem when your plants are small, cause the bastards will fed on the baby's roots and it will be left unfed and will die.
I got my gnats later in the pre flowering stage. I was using MG soil and it is known for this soil to have gnats in it.
I managed to kill all of them with Neem Oil. Just put some oil in a spray and spray the top soil, the pot and under the pot and most important, make sure you don't over water the soil, just let them dry good before watering. And spray with that Neem oil until no gnats. Advantage of this -> natural so no nasty taste in the buds and once dead, the gnats and larvae in the soil will act as a natural fertilizer
 

delvite

Well-Known Member

I'm growing for my Girl Friend's mom, and Her son was taking care of her Mother plants (Lemon Larry OG and Purple Kush). When I got the keys to the grow room, I opened the door only to find Powder Mildew, Spider Mites, and Fungus Gnats. I have conquered Spider Mites and Powder Mildew, using Neem Oil and SM-90. I'm failing horrible at controlling the Fungus Gnats their numbers have doubled. I have put DE(Diatomaceous Earth) on the top layer of soil. I've noticed the females have been laying eggs in the drainage holes in at the bottom of the pots. Should I just let the soil dry up in between watering?

found this..............................

Fungus Gnats


Fungus gnats like to feed on roots of the plants and organic matter. Adults and larvae live in moist, shady areas. The adults lay there eggs on top of the soil, near the base of the stem and takes about 4 days to hatch. The larvae will start by eating the root hairs of the plant then working their way up the plant, Fungus gnats like to eat organic matter so they will be stealing away nutrients from your plants, so its best to get rid of them completely. [color=red. Plants growing in rock wool are more prone to getting a more severe infestation than plants growing in soil. If your plants are affected during late flowering or close to harvest, please try to use the safest means of control to be safe to your health.


[B]Prevent and Control[/B]


Prevent indoor entry of gnats by making sure there is no open windows open without screens on. Aug is a bad time for them as they are worst that time of the year.


Put sticky traps on the soil surface to trap the gnats


Put potato slices on the surface of the soil. The larvae like it and will be drawn to it.. After about 4 to 5 days, remove the potato slices with the larvae. To get rid of them you can do a lot of things like either use a NO pest strip, neem oil or putting sand on the surface of the soil will suffocate the eggs and get rid of them as well. Tobacco juice kills them, and works well for re-occurrences!


They can be in or on the soil and can fly. In order to get rid of them you can use neem oil, sand or perlite on the surface again kills them, and no pest strips catch the ones that fly. A chemical product called Zone works very well and is very powerful and works well in Hydroponics/Aeroponics!
Other Products which can be used in Hydroponics/Aeroponics and soil are:




Safer Yard & Garden Insecticide


GNATROL( used in Hydroponics/Aeroponics in the water as well as soil),
Safer Sticky Stakes,
TR-11000 Pyrethrum.
PERMETHRIN dust
Mosquito Dunks


Organic Control


Natrasoap
Pest Oil
Neem Oil
Hot Pepper Wax
Doc's Neem Pest Soap
Sticky traps
Safer's Insecticidal Soap
Neem Oil
Neem 2

you seem to be winning the battle, hope this helps win the war :) Delvite
 

hexthat

Well-Known Member
Put potato slices on the surface of the soil. The larvae like it and will be drawn to it.. After about 4 to 5 days, remove the potato slices with the larvae. To get rid of them you can do a lot of things like either use a NO pest strip, neem oil or putting sand on the surface of the soil will suffocate the eggs and get rid of them as well. Tobacco juice kills them, and works well for re-occurrences!


Safer Yard & Garden Insecticide


GNATROL( used in Hydroponics/Aeroponics in the water as well as soil),
Safer Sticky Stakes,
TR-11000 Pyrethrum.
PERMETHRIN dust
Mosquito Dunks


Organic Control


Natrasoap
Pest Oil
Neem Oil
Hot Pepper Wax
Doc's Neem Pest Soap
Sticky traps
Safer's Insecticidal Soap
Neem Oil
Neem 2
In 45mins the lights go on, I will try some tobacco juice, with neem oil. I don't smoke tobacco but my girlfriend's brother's friends do so I'll be dumping the ash tray from now on. I have stopped the gnats from laying on the top of the soil with DE(Diatomaceous Earth), but they found the drain holes. I'll spray the drain holes with Hot Pepper Wax, Neem oil, tobacco Juice, and some kind of dish soap. I am going to pick up sticky traps next time I visit the grow shop. I am also going to let the soil dry up.

P.S. I feel fungus gnats are harder to get rid of then powder mildew or spider mites. Gnat babies are hiding in the soil where as PW and SB are visible.
 

perkele

Well-Known Member
:-P I remember now, when you said about the hot pepper :)) when I had my gnat problems I've tried that. Bought the hottest peppers I could find and made a soup out of them and added some hot paprika just to be sure. No tabasco cause there we have vinegar and don't want to mess with the pH of the plant (only with the one in the belly). Sprayed it on the soil and around, the gnats liked it...wasn't hot enough for them...and trust me it was a weapon that hot pepper spray I've made.
About tabaco juice...don't know anything, I just know that nicotine and fumes from cigarets or any kind of pipes it's harmful for the plant.
If your plants are big, I would just give it Neem (it's natural) and that's it...
How old are the plants? How long until finish?
 

perkele

Well-Known Member
In 45mins the lights go on, I will try some tobacco juice, with neem oil. I don't smoke tobacco but my girlfriend's brother's friends do so I'll be dumping the ash tray from now on. I have stopped the gnats from laying on the top of the soil with DE(Diatomaceous Earth), but they found the drain holes. I'll spray the drain holes with Hot Pepper Wax, Neem oil, tobacco Juice, and some kind of dish soap. I am going to pick up sticky traps next time I visit the grow shop. I am also going to let the soil dry up.

P.S. I feel fungus gnats are harder to get rid of then powder mildew or spider mites. Gnat babies are hiding in the soil where as PW and SB are visible.
indeed, they can be harder to kill, but they don't do that much damage like the spider mites. Again, the gnats are making damage to small plants that have small undeveloped roots. To bigger plants...not so much and anyways the life of a plant is not so long so if your plants are big and they are almost done...don't even bother with them
 

hexthat

Well-Known Member
indeed, they can be harder to kill, but they don't do that much damage like the spider mites. Again, the gnats are making damage to small plants that have small undeveloped roots. To bigger plants...not so much and anyways the life of a plant is not so long so if your plants are big and they are almost done...don't even bother with them
The fungus gnats came from the mothers my girlfriend's brother was taking care of, same with the spider mites and powder mildew. They are everywhere I'm spraying everything today with neem oil and sm-90. I'm a bit paranoid about TMV and my plants. I say they can get it so I won't be using tobacco juice.
 

hexthat

Well-Known Member
Today I checked everything and looks PW and SM free only problem is the FG. They spread from my veg room to the flowering room. I see about 50 flying around so I'm guessing all the roots of the mothers are getting ate right now... I'm gana water with neem oil....
 

hexthat

Well-Known Member
I over exaggerated I could only count about 10-15 flying around. They like to stay close to the plants. I watered with neem oil yesterday.
 

hexthat

Well-Known Member
BAMB!! Fungus Gnat free grow room, couldn't have done it without neem oil. Not a single Gnat can be found now.
 

hexthat

Well-Known Member
fungus gnats are back :sad:

I'm pretty sure its from my organic soil. Black Gold why you got to do this to me...... I'm going to use water with Bacillus thuringiensis a few times.
 

orgoglio

Member
HATE Fungus gnats! The old Canna terra bagged stuff used to come with hoardes of gnats, seems they got that under control....

I have had success with a soil drench of cedar oil. Good luck at keeping them away!
 

elkukupanda

Active Member
damm those fungus gnats... i'm telling you...
you know i tried putting sand over the soil.. like half an inch on my three gals... hmmm and some sticky pads... it was about 5 days ago and well i water every 2-3 days... at the moment i haven't seen too many around.. like 4 or 5? i want to try some perlite on top next if this doesn't work out...but will see... btw the sand sunk into the soil and made it a little bit more compact... so far is working... ill let you know again after a couple of weeks...
 

elkukupanda

Active Member
Ok, so after 7 days with sand on top of my soil.. fungus gnats gone... one thing to have into consideration.. if you put too much sand might compact down and block aeration... happened to one of my plants after 2nd watering... i realized because the plant wasn't growing too much and others were... nothing happened just a couple days with no optimum growth... anyways if sand compacts.. it will be hard as a rock so just take it out and stuff... perfect solution for gnats.. they gone.. woohoooooo
 

i.am.what.i.am

Well-Known Member
last grow i had a BAD fungus gnat problem during flowering. i was picking gnats out of all the bud with tweezers. take care of your gnat problem BEFORE flowering. cause its a bitch to get the gnats off when they get stuck in the sticky trichomes. what i did was put at least an inch of sand on top of the soil AND let the soil get bone dry in between waterings AND put up those sticky fly traps AND set out little dishes of apple cider vinegar to attract and drown the little fuckers. after doing that, i saw no more gnats. This grow, I am seeing them again but plants are in veg. I know now how to stop them. The Sand trick is what works best in my opinion....the little fuckers can't break thru the sand to breed and eventually die
 

TapuRolls

Member
Did any of you guys seen larvae's of the fungus gnats in your grow?I am possibly dealing with a fungus gnat infestation but i aint sure.Yday when i watered my plant ive seen some small white larvae pumping out from the soil, once the water of draining they went back in the soil and pretty fast.After around 5 minutes on the next watering i tried to kill some of them but they were jumping around like crazy :D.Did some research and found out that the jumping larvae's might be Sprintails which shouldnt be that bad,although a couple of hours ago i tried scratching the surface of my soil(like 2-3 cms deep) and out of my surprise i found 2 bugs crawling around(small black winged bugs, surely looking like fungus gnats). Now from what ive readen Springtails are wingless, these 2 that i caught do have wings and moce pretty fast.I havent noticed any flying gnats in the grow closet, these 2 are the first ones ive seen and "murdered" them.My plant is in veg state, going towards 3rd week now and im thinking to use the sand solution although i do not want to rush with any decision.If any of you guys had any similar situations when watering with fungus gnats or little white larvae's jumping around like mad right away after watering let me know, probably will help me out to indentify what im dealing with.
 

333maxwell

Active Member
Guys.. gals.. soil growers..

Just stick a few sticky traps up and water your soil with 1/2 cup h202 (3%) to a gallon of water.

Yes your soil will foam a bit (that is half the fun.. it aerates it well and will dry out quickly after that treatment).

No it wont hurt your plants (people can debate short term impact on roots, it is even in the worse case scenario better than a legion of root munching gnat larva.

Sticky traps get's em in the air. H202 kills all larva INSTANTLY in soil.

Next day plant looks better, healthier, it smiles at you and says 'I can dig it'.


---

Do your own research and never take my advice for anything.. but I can tell you I have done this personally for decades when the lil buggers pop up out of nowhere.. I take care of the problem finally and instantly for little money and have never had a negative result.. except it get's kind of lonely when your little flying friends just leave you so quickly without saying goodbye.



IF you have a million plants it is hard to do it though unless you water them all on the very same day within a few minutes of each other.. both rooms.... lest the lil bastids go breed in soil you already treated.. it isn't poison.. it only kills the ones are there that minute then the oxygen in the o2 releases.. 5 minutes later new ones could come and breed (if they were in the mood that quickly).. so if you have a lot of plants, maybe h2o2 would present a logistical problem.





Just one train of thought some may want to do their own research on. It may or may not help. I don't like to screw around and I don't like any poisons or chemicals if it can be avoided.. gnats are SUPER easy to kill with only the h202 and sticky traps.
 
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