How to Get Rid of Black Gnats in House Plants

Keep your houseplants helathy by getting rid of black gnats.

Black gnats, also known as fungus gnats, feed off the leaves, soil and roots of houseplants. Fungus gnats appear as small white maggots, and then they mature into black insects with wings. The gnats can spread diseases such as root rot from one plant to another. The gnats are not a threat to humans or pets, but they are a nuisance. You can get rid of the black gnats with items you have around your home to prevent them from killing your house plants.

Things You'll Need

• Potato slices
• Jars
• Aluminum foil
• Plastic wrap
• Needle
• Citronella candle

Instructions

1. Let the soil on the houseplant dry completely. Avoid watering the plant until the top 1 to 2 inches of the soil feels dry. This prevents the black gnat eggs from hatching, and the gnats will not be attracted to the plant.

2. Slice a potato and place it on top of the soil. Leave the sliced potatoes on top of the soil for four to five days. You will notice larvae crawling on the potatoes. Remove the potatoes and throw them away.

3. Set up jars filled with vinegar if you still notice black gnats flying around. Cover the top of the jars with aluminum foil or plastic and poke small holes with a needle. The small holes will allow the gnats to enter the jar, but they will not be able to escape.

4. Light citronella candles around the houseplants. Gnats do not enjoy the citronella scent and they will stay away from the plants and die when they no longer have a food source.

References

• Colorado State University Extension: Fungus Gnats as Houseplant and Indoor Pests
• University of Connecticut: Tips on Managing Common Bedding Plant Insects and Mites Pests
• Ask the Exterminator: Where do Gnats Come From?
• Colorado State University: Managing Houseplant Pests
• University of Florida: Houseplant Arthropod Pest Management
• University of California: Fungus Gnats, Shore Flies, Moth Flies, and March Flies