How to deal with fungus gnats?

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Looks like my schefflera has fungus gnats, I've been seeing some little bugs fly around a bit, and when looking at the fertilizer I saw the larvae.

Rather than keep them around, I'm curious if anyone can make suggestions for how to get rid of them, since it's three months from repotting time. I figure I will treat my other tropicals as well to ensure I'm not missing anything, but let me know if they don't spread much. I've been seeing them here and there for a few weeks now, I'd say, and just now realized what they were and where they were coming from.
 

Forsoothe!

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Once they hatch, they're hard to catch or kill. The black ones spend most of their time walking around on the soil surface and the white winged ones fly around, mostly they like to fly in your face and eyes. They have a short lifespan. They find a spouse, do obscene things and lay their eggs in your soil (media, whatever). They like damp soil. Buy any horticultural oil, follow directions for mixing and drench the soil which will kill their eggs and larva (which eat roots). Presto!
 
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Once they hatch, they're hard to catch or kill. The black ones spend most of their time walking around on the soil surface and the white winged ones fly around, mostly they like to fly in your face and eyes. They have a short lifespan. They find a spouse, do obscene things and lay their eggs in your soil (media, whatever). They like damp soil. Buy any horticultural oil, follow directions for mixing and drench the soil which will kill their eggs and larva (which eat roots). Presto!

So like Neem Oil? I have that!

diatomaceous earth powder will kill the larvae

Awesome, I'll take a look at that as well!
 

hinmo24t

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as stated. those mosquito bits from amazon are proven. i use them fairly liberally mixed in soil (some just top dress) and considering i have about 75 houseplants and basically no gnats, they work. also, neem mix or hydrogen peroxide 3%, half cup to full spray bottle or watering jug
 
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Chopsticks Mr miyagi style or better soil and watering routine, I use fully inorganic soil and never have a problem with fungus gnats they love wet organic soils

yeah, i’m getting my plants out of organic soil this year for sure
 

HorseloverFat

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Also.. if you make sure ALL indoor containers are filled with inorganic soil.. they WONT become an issue... they smell wet “earth”.. they reproduce in wet “earth”... if you have no dirt/bark/moss in your substrate.. they are not intetested.
 

Lutonian

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Also.. if you make sure ALL indoor containers are filled with inorganic soil.. they WONT become an issue... they smell wet “earth”.. they reproduce in wet “earth”... if you have no dirt/bark/moss in your substrate.. they are not intetested.
See post #8 for details 😉
 

Wires_Guy_wires

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Combating gnats are like a trying to solve a vulture problem.. You can scare them away, shoot them dead, but the best fix is to stop the corpses from stacking up. If there's no tasty meal, then they wouldn't bother you.

I've been advising gardeners for over a decade now, and this seems to be one of the hardest concepts to grasp for a lot of people.
Gnats are a symptom, a result, not a cause. It's quite literally in the name 'fungus' gnats. They pop up when there's dead stuff decaying. Some plants do well in decaying matter, most do not.

A friend of mine has been dealing with gnats for over a year now. She calls me a shitty gardener, a poor plants-person. Because I can't fix her issue for her.
When I keep her plants in my house, the gnats disappear within a week or two. No issues whatsoever.
When she gets them back, the gnats come back within 10 days. She asked me a hundred times what kind of killer stuff I use..
The answer is always "Less water, more air, better soil".
She doesn't believe it. When her plants die, she blames the gnats because their larvae have invaded every part of the plant.
She found maggots in a corpse and blames the maggots..

 
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diatomaceous earth powder will kill the larvae

I had a friend swear on this stuff this morning so I'm going to start here since it's organic

Combating gnats are like a trying to solve a vulture problem.. You can scare them away, shoot them dead, but the best fix is to stop the corpses from stacking up. If there's no tasty meal, then they wouldn't bother you.

I've been advising gardeners for over a decade now, and this seems to be one of the hardest concepts to grasp for a lot of people.
Gnats are a symptom, a result, not a cause. It's quite literally in the name 'fungus' gnats. They pop up when there's dead stuff decaying. Some plants do well in decaying matter, most do not.

A friend of mine has been dealing with gnats for over a year now. She calls me a shitty gardener, a poor plants-person. Because I can't fix her issue for her.
When I keep her plants in my house, the gnats disappear within a week or two. No issues whatsoever.
When she gets them back, the gnats come back within 10 days. She asked me a hundred times what kind of killer stuff I use..
The answer is always "Less water, more air, better soil".
She doesn't believe it. When her plants die, she blames the gnats because their larvae have invaded every part of the plant.
She found maggots in a corpse and blames the maggots..


yeah, for sure. I've kept bonsai for a few years, but it's only in the past year that I've started getting considerably deeper with them. I realized pretty quickly that the soil my trees were in was no bueno. I'm just limping along til I can repot. In this instance it's a tropical, so it's a bit aways.
 

Grovic

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Looks like my schefflera has fungus gnats, I've been seeing some little bugs fly around a bit, and when looking at the fertilizer I saw the larvae.

Rather than keep them around, I'm curious if anyone can make suggestions for how to get rid of them, since it's three months from repotting time. I figure I will treat my other tropicals as well to ensure I'm not missing anything, but let me know if they don't spread much. I've been seeing them here and there for a few weeks now, I'd say, and just now realized what they were and where they were coming from.
If you don't want to use chemicals, I've used a solution of water and hydrogen peroxide with very satisfactory results.
I water my plants with the solution once a week when the gnats start to appear, just the soil, misting is not necessary, pretty effective, usually two or three applications are more than enough. You'll see results immediately after the first one.
I use the brown bottle you get at any Walmart or CVS.

1614291906058.png

The table came from this website:

 

Grovic

Mame
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If you don't want to use chemicals, I've used a solution of water and hydrogen peroxide with very satisfactory results.
I water my plants with the solution once a week when the gnats start to appear, just the soil, misting is not necessary, pretty effective, usually two or three applications are more than enough. You'll see results immediately after the first one.
I use the brown bottle you get at any Walmart or CVS.

View attachment 356740

The table came from this website:

Also, clap the shit out of the ones you see flying, lol.
 
Messages
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Eastern MA
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If you don't want to use chemicals, I've used a solution of water and hydrogen peroxide with very satisfactory results.
I water my plants with the solution once a week when the gnats start to appear, just the soil, misting is not necessary, pretty effective, usually two or three applications are more than enough. You'll see results immediately after the first one.
I use the brown bottle you get at any Walmart or CVS.

View attachment 356740

The table came from this website:


Awesome, thank you - I have peroxide and can give this a shot as well!
 
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