How to Kill Fungus Gnats on Indoor Vegetables

Mix 2 teaspoons of insecticidal soap in 1 quart of water. Water your plants with the mixture at least once a week. Allow the soil to dry out between watering.

Place index cards smeared with honey or a sticky substance around your plants. The adult fungus gnats get caught on the traps and die. This also reduces the number of breeding gnats, effectively cutting down on the number of gnat eggs developing and hatching in the soil.

Let the soil dry between each watering. Fungus gnats thrive in moist, wet soil. Allowing the top layer of soil to dry out before watering the plant again kills any eggs growing in the soil.

Water your plants less often. Give your plants only the amount of water it needs to sustain itself. Water your indoor plants no more than once a week, to prevent fungus gnats from living in the soil.

Repot your plants in fresh soil. Remove each plant from its container and remove the extra soil around the root ball. Place the plant in another container and fill it with fresh soil.

Remove and clean up organic debris growing around your plants. Fungus gnats eat decaying organic debris in the soil. Removing this food source starves the fungus gnats.

Apply hydrogen peroxide to the soil to kill the fungus gnats. Allow the soil to dry out for a few days before adding the peroxide, then mix one part hydrogen peroxide with one part water, and pour it directly on the soil.

Place all fruits and vegetables in the refrigerator. Fungus gnats have a life cycle of about four weeks, so removing the insect's food source starves them to death, and prevents them from reproducing.

Add 2 tablespoons of liquid soap to a bowl of vinegar and place it in an area where the fungus gnats can get to it. The vinegar attracts the gnats to the bowl, where they drown in the mixture.

Pour vinegar in a bowl and cover it with plastic wrap. Poke tiny holes in the plastic wrap with a pin or needle. The vinegar draws the fungus gnats inside, where they get trapped and die.