How to Get Rid of Tiny Flies on Indoor Plants

Do you see small flies around your indoor plants? These tiny flies are probably fungus gnats, a common issue. Although they don't harm the plants directly, their larvae can. Larvae eat plant roots and soil, making plants weak and stressed. It's important to act quickly to save your plants. But how can you get rid of these pests? This article will show you methods to spot, stop, and remove fungus gnats from your home.

What Are Fungus Gnats

Fungus gnats are very small insects that look like tiny mosquitoes or fruit flies. They are known for their long legs and clear wings. These bugs like to live in damp, rich soil. This is where they lay eggs and their young ones eat plant roots and fungus.

Adult gnats don't last long, around a week. But during that time, a female can lay 300 eggs. This means their numbers can grow fast. Too many of them can harm your indoor plants if you don't stop them in time.

These insects are really small, just 1/8" long. The adults don't eat plants, but their babies do. The larvae can slow down or stop the growth of plants that are still young. They do this by eating plant roots and the fungi in the soil.

Approximately 1/8" long
Resemble tiny mosquitoes or fruit flies, with long legs and transparent wings
Thrive in nutrient-rich, moist soil of houseplants
Life Cycle
Adult gnats live for about a week but can lay up to 300 eggs, leading to rapid population growth
Larvae feed on organic matter, plant roots, and fungi, potentially stunting plant growth

Signs of a Fungus Gnat Infestation

The first sign of a fungus gnat infestation is often the sight of adult flies around your houseplants. You'll notice them because they fly in a zig-zag and hover close to plants. You might also see the larvae, which are small and black-headed, moving around in the soil. It's easy to spot them by gently stirring the soil.

Plants showing stress, like wilting or yellowing leaves, might also indicate an issue. These symptoms could mean the gnat larvae are damaging the roots. These gnats can lay 300 eggs per female and mature in only 3-4 weeks, causing quick infestations.

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Fungus gnats, though not great at flying, can spread rapidly, especially in winter when the air is wet. Quickly addressing any signs of an infestation is vital. If left unchecked, they can harm your plants significantly.

Fungus Gnat Facts
Life Span
About 1 week
Egg Laying Capacity
Up to 300 eggs
Life Cycle Duration
3-4 weeks
Preferred Habitat
Moist, decaying organic matter in soil
Feeding Habits
Larvae feed on fungi and plant roots, reducing nutrient uptake

Spotting a fungus gnat infestation early is key to stopping it. By acting fast, you can stop the gnats from harming your plants. This proactive step ensures your plants stay healthy and grow well.

How to Get Rid of Tiny Flies on Indoor Plants

Getting rid of pesky fungus gnats on your indoor plants can be frustrating. But, there are many methods to get rid of them. You can make homemade traps, use sticky yellow traps, or set out cider and vinegar. These attract the gnats and drown them.

Fungus gnat larvae are tiny, about 1/4-inch long. They have a shiny black head and a clear, slim body. They like light and you might see them near plant-filled windows. It's key to know they're different from fruit flies, which are lighter colored.

  1. Create a trap by mixing sugar and water with a bit of dish soap. This sticky mix will pull in and trap the adult gnats.
  2. Using sticky yellow traps can capture adult gnats, helping to stop the infestation.
  3. Another trap is a cider or vinegar mix with a little soap. Put this in small cups near plants to attract and kill the pests.

If the gnats are really bad, try using beneficial nematodes. They eat the larvae and help stop the cycle. You can also use chemicals like hydrogen peroxide or neem oil. These kill gnats in both their larvae and adult stages.

To help prevent gnats, let the soil around your plants dry out between waterings. Use pots with good drainage and only clean potting mix. Doing regular checks and taking action early can keep your plants gnat-free.

Introducing Beneficial Nematodes

Adding beneficial nematodes to your indoor plants can keep them healthy. These tiny worm-like creatures eat fungus gnat larvae. They don't harm your plants, pets, or you. So, they are a great help for indoor gardens.

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Follow the given directions to use them right. This can get rid of gnat problems and keep new ones from happening. At Natures Good Guys, shipping can take 1-3 days. They also offer fast shipping options, but not same-day delivery.

People have been using nematodes to control pests for more than fifty years. One type, Steinernema feltiae (Sf), is great for gnats and other bugs too. You might need about 5 million of them for every 1,600 square feet. But this amount changes depending on the pests you're battling.

To get the best out of nematodes, apply them early in the morning or late in the day. Do this when it's cool and without sunlight. This strategy helps the nematodes live and effectively hunt down pest larvae.

Nematode Species
Target Pests
Steinernema feltiae (Sf)
Fungus gnats, beet armyworms, black cutworm, cabbage maggots
Heterorhabditis bacteriophora (Hb)
Ant and Japanese beetles, various other insects
Steinernema carpocapsae (Sc)
Fleas, armyworms, fruit flies, flea larvae, wood borers
Steinernema kraussei (Sk)
Weevils and related pests
Steinernema riobrave (Sr)
Armyworms, black vine weevils, Japanese beetle grubs, pests of citrus and orchards

Chemical Control Methods

While choosing natural methods is often better, chemical options are sometimes needed. Some products with hydrogen peroxide, neem oil, and pyrethrin fight both larvae and adult fungus gnats. It's key to use these products right, to keep your plants safe. These options quickly kill fungus gnats when natural ways don't work well.

Bacillus thuringiensis subsp. israelensis (Bti) is a top chemical for dealing with fungus gnats. It kills larvae by stopping their digestive systems. Products with imidacloprid, like a systemic insecticide, also get rid of larvae by being absorbed into the plant.

Active Ingredient
Target Life Stage
Bacillus thuringiensis subsp. israelensis (Bti)
Highly effective, disrupting the larvae's digestive system
Effective, as a systemic insecticide absorbed by the plant
Hydrogen peroxide
Larvae and adults
Moderately effective, can help control both stages of the pest
Neem oil
Larvae and adults
Effective, disrupting the life cycle and repelling the pests
Highly effective in targeting the adult stage of fungus gnats

When using chemicals, always follow instructions and be safe. A mix of natural and chemical steps might be best for stopping fungus gnats in your plants.

Insecticidal Sprays

Insecticidal sprays with pyrethrin can quickly kill adult fungus gnats. These sprays are made from plants and are toxic to many bugs that fly. Using them right, as the label says, can stop the gnats from making more.

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Target the soil and leaves of the plants you treat. Keep spraying them as the label instructs until the bugs are gone. Remember, these sprays work fast but aren't the best for long-term bug control. They can also hurt bugs that are good for plants.

Active Ingredient
Safety Considerations
Pyrethrin Spray
Effective in eliminating adult fungus gnats on contact
Plant-derived, but can be toxic to beneficial insects
Azadirachtin Spray
Disrupts the life cycle of fungus gnats, targeting larvae and adults
Derived from neem oil, considered a more natural option
Bacillus thuringiensis (Bti) Spray
Bacillus thuringiensis subspecies israelensis
Effective in controlling fungus gnat larvae
Targeted biological control, safe for people, pets, and beneficial insects

Always read and follow the instructions on the spray you choose. Keep yourself and your surroundings safe while using it. Also, think about other ways to control gnats, like better soil drainage, for long-term success with your plants.


Fungus gnats might look small, but they can become a big problem for those who love indoor gardening. It's vital to spot the infestation early, then act fast. By using a mix of natural and chemical methods, you can beat these tiny plant flying insects. This way, you keep your indoor plants safe and healthy. With the correct steps, you can have a beautiful, pest-free garden inside.

To deal with fungus gnat invasions, you need a plan that tackles every part of their life cycle. Start with preventing them. You can do this by watering your plants carefully, choosing the right soil, and keeping it dry. Adding beneficial bugs and using certain sprays and traps are also good ways to fight off these gnats.

Being alert and using a variety of control methods is key to beating fungus gnats. By staying on top of your plant care and watching out for signs, you can win this battle. Equipped with the right information and tools, you can create a great indoor garden without the nuisance of these pests. Your hard work will pay off, and your plants will thank you with their beauty.

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