How to Kill Soil Gnats Organically
- 1
Fungus gnat larvae are attracted to the potato wedge.Stockbyte/Stockbyte/Getty Images
Slice a potato into wedges about 1/4 inch thick. Slide one potato wedge into each potted plant to a depth of 1/2 inch. Leave the potato wedges in place. - 2). Pull the potato wedges out the next day, along with some of the soil that's stuck to it. Check for fungus gnat larvae on the potato. Discard the potato wedges in a sealed trash bag.
- 3). Change the potting soil in the plants that are infested with fungus gnats and larvae. Discard the infested soil in the sealed trash bag.
- 4
Overwatered plants provide prime conditions for fungus gnats.Jupiterimages/Goodshoot/Getty Images
Ensure that the pots you use have drainage holes on the bottom. Water the plants only when the soil is completely dry. Use a plant tray underneath the pots to catch excess water. Drain the standing water to discourage fungus gnats. - 5). Trim away decaying leaves, flowers and other organic material that attracts fungus gnats. Discard in the trash.
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