How Do I Get Rid Of Gnats In My Potted Plants?. The soil will start to oxidize a few minutes after application. Moist breeding grounds for gnats include food spillage, moist potting soil, overwatered grass or plants, garbage cans, puddles in kitchen or outside your house, leaky pipes under the.
Make sure to watch for fungus gnats over the first couple of weeks. The fungus gnat will be killed by contact with hydrogen peroxide. This will prevent the nymphs from entering the soil and protecting your plant’s root systems.
