How To Get Rid Of Fungus Gnats. Moreover, it can eliminate the pest at all stages of. If you see large numbers of fungus gnats, then one organic insecticide to.
Remove the top layer of the soil, larvae, and potatoes. To make a solution that will kill fungus gnats, mix 1 cup of sugar and two teaspoons of active dry yeast in a small jar with 1 cup of hot tap water. Isolate new and infected plants.