BTI, which is short for Bacillus thuringiensis israelensis, is deadly to mosquito larvae and fungus gnat larvae but harmless to other living things. The bacterium is nature’s way of keeping fungus gnat and mosquito populations down. Fortunately, BTI has no effect on other insects (such as bees and butterflies). Nor does it harm animals, fish, birds, plants, pets or people.

BTI is the active ingredient in Mosquito Bits®, which is approved for the biological control of fungus gnats. Mosquito Bits may be used on houseplants, vegetables, herbs and home mushroom beds. 

To kill fungus gnats, mix 4 tablespoons of Mosquito Bits® in one gallon of water. Let the Mosquito Bits® soak for 30 minutes. Then simply skim off the floating granules and shake or stir the water. The resulting BTI-infused water can now be used to water the potting mix of any container-grown plant. The BTI in the water will kill fungus gnat larvae in the soil to break their reproductive cycle. Repeat this process weekly for three weeks. If fungus gnats return, just repeat the treatment cycle again.

8 ounce package.