Fungus gnats can be a pesky problem for houseplants, but there are several effective ways to control them. These tiny flies thrive in moist soil and feed on organic matter and plant roots. Here’s some steps that you can take to manage and eliminate them:

1. Let the Soil Dry Out

• Fungus gnats lay their eggs in damp soil, and their larvae need moisture to survive. Allow the top 1-2 inches of soil to dry out completely between waterings. This disrupts their life cycle.
• Be cautious not to overwater your plants—check their specific needs, as some tolerate drier conditions better than others.

2. Use Sticky Traps

• Place yellow sticky traps near your plants to catch adult gnats. The bright color attracts them, and the adhesive keeps them stuck. This won’t eliminate the problem entirely but helps reduce the population and monitor their numbers.

3. Apply a Soil Drench

• Hydrogen Peroxide Solution: Mix 1 part 3% hydrogen peroxide with 4 parts water. Water your plants with this solution to kill larvae in the soil. It’s safe for most plants but test it on a small area first.
• Neem Oil: Dilute neem oil according to the instructions and use it as a soil drench. It’s a natural pesticide that can disrupt the gnat life cycle.

4. Add a Physical Barrier

• Cover the soil surface with a layer of sand, gravel, or decorative pebbles (about ½ inch thick). This prevents adult gnats from laying eggs in the soil and makes it less hospitable for larvae.

5. Use Beneficial Nematodes

• Introduce Steinernema feltiae, a type of beneficial nematode, to the soil. These microscopic worms attack and kill gnat larvae without harming plants or humans. You can find them at garden centers or online—just follow the application instructions.

6. Trap Adults with a DIY Solution

• Set up a trap using a small bowl filled with apple cider vinegar, a drop of dish soap, and a bit of water. Cover it with plastic wrap and poke tiny holes in the top. Gnats are attracted to the vinegar, enter through the holes, and drown.

7. Maintain Good Plant Hygiene

• Remove dead leaves, debris, or standing water from pots and trays. Overly soggy conditions encourage gnat infestations.
• If the problem persists, consider repotting the plant with fresh, sterile potting mix to eliminate any remaining eggs or larvae.

Prevention Tips

• Use well-draining soil and pots with drainage holes.
• Avoid letting water sit in saucers for too long.
• Quarantine new plants to ensure they’re not bringing gnats into your collection.

Consistency is key—combine a few of these methods and monitor your plants over a couple of weeks to break the gnat life cycle. If you’ve got a stubborn infestation, let me know, and I can dig deeper into specific plant types or solutions!