Natural Remedies for Fungus Gnats

[emilywilson54]

Does anyone have a natural treatment for Fungus Gnats? The orchids in question are in bloom, so I don't want to re-pot them quite yet.

Thanks

[orchidegg]

I would get some carnivorous plants, sundews (Drosera), work like a charm. I grow mine inside right next to my orchids and haven't had a problem since I got them. If you don't like the natural predator idea I'd get some BT (Bacillus thur-something) solution works too.

[Jerry Delaney]

You might look for some beneficial nematodes, Emily. The one you are looking for is Steinernema feltiae. If you Google "beneficial nematodes" you will find a number of sources for them. There are other species but this one is the best to use for fungus gnats. If you are going to try BT, I think I would look for a product containing BTi. Many of the BT strains used show good efficacy only on caterpillars.

[Ethan]

Hi, Emily-

Just wanted to give my two cents worth. Fungus gnats can only survive in soil that stays constantly moist. They lay their eggs in soil and the larva hatches and lives there until they turn into the gnat form. If you allow your soil to dry out, the larva will die and not be able to reproduce.

I used to have a horrible problem with fungus gnats and I discovered they were coming from the potting soil I was buying. I was buying it wet. I started buying potting soil that was completely dry to make sure I wasn't introducing any new ones into the g/house.

I also started letting the soil in my potted plants dry out a little more before re-watering. And just like magic, my fungus gnat population was under control!

Also, fungus gnats generally do no harm to the plant at all...they are just a nuisance. You could also try the little yellow sticky traps that you can usually find at a garden center. They work pretty well as the gnats are attracted to the color yellow.

[camille1585]

I agree with Ethan, letting the medium dry out more should help. I had a big fungus gnat problem in nov-dec, and so I started to let the plants get really dry for a few days between waterings. That broke the cycle, and now there are no more gnats!!
I would also go after the flying adults with a spray bottle of soapy water. The soap sticks their wings down so they can't fly, and they drown in the water.

[Gin]

Here is my solution It is a Butterwort, Sundews also work well ..

[cirillonb]

I had fungus gnats and bought some BT (a bacteria that the grubs eat and die) at great expense only to have them succumb to treating the soil with a soap solution for creepy crawly critters. If you have a big problem you can buy BT at RePotMe they have a cutsy trade name for it. The mosquito dunks are BT available at garden centers. I have no precise recommendation for their dilution, I guess a quarter of a dunk per gallon would be ok.
BT is "organic" and a natural method of pest control
Nick

[cb977]

You can make your own sticky traps by using any piece of yellow plastic, cut into strips or whatever shape you'd like and coating them with Vaseline. Then hang them near your plants or stick them into the side of the pot. The Vaseline acts as a glue and they get stuck to it.

[brush]

I need some clarification on fungas gnats. Are the adults those little black flies , the size of a fruit fly , that fly around your plants? And the little gnats that are in the soil , are they little white things you can barely see , but when you water your plants you can see them in the water and they do jump a bit too? Feedback anyone?

[cirillonb]

Originally Posted by brush

I need some clarification on fungas gnats. Are the adults those little black flies , the size of a fruit fly , that fly around your plants? And the little gnats that are in the soil , are they little white things you can barely see , but when you water your plants you can see them in the water and they do jump a bit too? Feedback anyone?

Yes
Nick