How to Get Ride of Gnats in a Household Plant?

Apply a pyrethroid-based insecticide with the active ingredient bifenthrin, cyfluthrin or permethrin over the houseplant to rid your houseplants of gnats. Follow label directions for application rates.

Pour 2 tbsp. of dishwashing soap in 1 qt. of water and add the solution to a spray bottle. When sprayed over the houseplant, the solution suffocates the gnats and coats different parts of the plant, preventing infestations. However, this is a short-term control method that requires frequent application.

Hang yellow sticky traps around the edges of indoor pots and under each plant’s canopy. The yellow traps attract adult gnats including females, reducing the number of eggs and larvae. Check the traps every other day and replace them as necessary.

Allow the top 2 inches of potting medium to dry out between watering. Because adult gnats, gnat eggs and larvae thrive in excessively moist soils, allowing the soil to dry affects their development and survival.

Place a shallow bowl or container near the houseplant. Pour distilled white vinegar into the container, and add three drops of dishwashing soap to the container. Mix the solution with a spoon and let it settle. Attracted to the vinegar, the gnats that fly close to the solution drown due to the soap. Replace the solution regularly.

Use Bacillus thuringiensis var. israelensis insecticide as a soil drench to kill the larvae of gnats in the soil. Depending on personal preference, use a prepared liquid formulation over the soil, or spread granules and water the pot deeply to dissolve the ingredients and release them in the soil.

Sprinkle a 1/2-inch layer of rough, sterile sand on the potting soil to prevent adult gnats searching for perfect breeding grounds from laying more eggs. Avoid using outdoor sand that might be infested with gnats and other bugs.