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How to Use Mosquito Dunks to Control Gnat Infestations in Houseplants

flower in the pot image by AGphotographer from

Fungus gnats are a common pest for various houseplants. Fungus gnats look like little black fruit flies. Once the fungus gnats find your houseplants, they will quickly get out of control. The Mosquito Dunks product contains Bacillus thuringiensis israelensis (BTI for short). BTI has the power to kill more than just mosquitoes. It can also get rid of those pesky fungus gnats.

Put on a pair of plastic gloves before working with Mosquito Dunk. It can cause skin irritation in humans.

  • Fungus gnats are a common pest for various houseplants.

Cut the dunk in to quarters. Keep the knife you use with the Mosquito Dunks separate, so that you never use it for food.

Set 1 quarter of a dunk in 1 gallon of water and allow it to mix with the water naturally overnight.

Pour this treated water in a watering can and use it to water your houseplants.

Repeat once per week to keep the fungus gnats away.


Wash your hands with soap and water immediately after using the Mosquito Dunk.

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