Damn Gnat Flies

[Hooter]

Crush mosquito bits and mix into top inch of soil. Use fox farms don't bug me on top of soil and at drainage areas of pot after watering. Yellow sticky traps to collect adults. Stay on top of this and you break the life cycle in about a week. Don't over water. I have had complete eradication. For what it is worth.

 

[Jhhnn]

No compost in the nearby environs? You must be kidding, right?

What I meant was that if you have a open compost pile next to a greenhouse then chances are you will get fungus gnats if the conditions are suitable for them. Is that a sealed compost unit? If so then fungus gnats won't be a problem I'd imagine.
If you grow indoors in a cupboard, wardrobe, a room or the whole house and there's an open trash can in the house that has lots of fruit peels then chances are that you will get fungus gnats laying in the soil of your pot plants....unless you use one of the many chemicals suggested in the this thread or simply use horizontal air movement around the pots.

Compost needs air, so it's not sealed. For my purposes, fungus gnats are only an occasional annoyance now that I've figured out Gnatrol. What comes out of the tumbler is black gold.

 

[DocTim420]

Of course, the perfect egg laying material for a female FG is moist, rich organic material containing a good supply of fungi (hence the name "FUNGUS gnat"). Which, coincidentally are the same requirements for quality composted matter.

 

[KIS]

https://www.kisorganics.com/blogs/news/97755777-fungus-gnat-treatment