Buzz
Fungus gnats can cause significant damage by feeding on fungi, rotting plant material, roots, and leaves. Image credit: Debbie Maize / Getty Images / Dorling Kindersley.You carefully water, fertilize, and provide your plants with ample natural light. However, just a few weeks of overwatering can invite swarms of these unwelcome pests. Don't worry! There are many affordable and effective fungus gnat treatments to try.
What Are Fungus Gnats?
Fungus gnats are tiny, measuring about one-eighth of an inch, with dark grey or black bodies, slender wings, long legs, and antennae. Though their life span is brief, they cause damage by feeding on algae, fungi, decaying plant matter, and plant roots and leaves.
These pests don't travel far and usually remain around the plants they infest. Fungus gnats are particularly active in the late fall and winter months, often found buzzing around indoor plants. Check here for ways to eliminate this bothersome pest.
Fungus Gnat Life Cycle
Despite their short lives, fungus gnats can infest your potted plants and invade your space. From egg to adult, they typically live 3 to 4 weeks, spending most of their time on or in the soil surface [source: Planet Natural Research Center]. However, in their brief lives, adult gnats can lay up to 300 eggs, leading to troublesome infestations.
The eggs hatch in as little as four days, though the larvae stage lasts much longer. The larvae live in moist soil for around 12 days before becoming pupae for 4 to 6 days [source: Hernandez]. Adult fungus gnats grow up to a quarter of an inch and spend about eight days flying around the plant where they were born, laying more eggs.
Treating Fungus Gnat Infestations
Confirm that the pests are indeed fungus gnats by using the raw potato test. Place a slice of raw potato on the soil next to an infested plant. If they're fungus gnats, you'll see them gather around the potato within hours. Lifting the potato should reveal the larvae underneath.
- Insecticides: Drench the soil with microbial insecticides like bacillus thuringiensis (Bt), a powerful solution to eliminate fungus gnat larvae.
- Sticky Traps: Position yellow sticky traps near the infested plant. These 3-by-5-inch traps attract and capture many fungus gnats, though they might not catch all of them.
- DIY Liquid Traps: Create a homemade trap by filling a small bowl with warm water, apple cider vinegar, sugar, and a few drops of dish soap. This will draw in and kill fungus gnats.
- Diatomaceous Earth: This natural substance, made from the fossilized remains of aquatic diatoms, repels fungus gnats. Sprinkle it around the base of your plant to deter them effectively.
Preventing Fungus Gnats
Although fungus gnats are harmless to humans, they can seriously damage your houseplants. They're not the most pleasant companions either, which makes it wise to focus on prevention to avoid dealing with them in the first place.
Luckily, preventing fungus gnats from invading your cherished houseplants is relatively easy. Try the following methods to keep your home gnat-free:
- Avoid overwatering: Overwatering is the primary cause of fungus gnat infestations in plants. These pests thrive in overly moist soil, so letting the soil dry out slightly between waterings can help keep them at bay.
- Sand: Adding a half-inch layer of sand to the surface of your plant's soil can also stop fungus gnats. It not only helps eliminate an active infestation but also prevents future ones from occurring.
- Keep your drain clean: Fungus gnats can also breed in your sink drain. To prevent this, clear away any organic material and regularly clean the drain to keep it gnat-free.
Enjoy Pest-Free Plants Now!
You've invested time and money in your houseplants, and you work hard to keep them healthy. While they don't pose a threat to humans or pets, fungus gnats can stunt plant growth and contribute to root rot [source: University of California Agriculture & Natural Resources].
Don't let these easily-eliminated pests harm your indoor plants. Take action with the tips above, and bid farewell to fungus gnats once and for all.
