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How to get rid of fungus gnats

10 years ago

Periodically I read posts about fungus gnats and how to get rid of them. They can be very annoying. They come in potting soil and it doesn't matter if it's expensive soil or cheap stuff.

Getting rid of fungus gnats is easy. Fungus gnats spend most of their life in the soil. They emerge as flies to mate and lay eggs in the soil so killing the flies accomplishes nothing. The eggs hatch and become larvae. The larvae feed on debris in the soil and plant roots.

Take care of the eggs and larvae and you'll have no more fungus gnats. Mix a 1/2 to 1 teaspoon of insecticidal soap with a quart of water --no more soap than that you don't want to burn the roots only get rid of the gnats. Water the soil of the plant with it. You don't need to make the soil sopping just water a it so the soil is damp. You can always go back and do it again. The soap kills both eggs and larvae and won't hurt the plant if mixed right. If I do get them I usually only have to do it once and they are gone but there is no harm in doing it again if you don't get them all.

As a precaution I water the soil with the soap solution when I prepare it for planting and then I never have fungus gnats

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