The most common backyard gnats are fungus gnats. Found in areas of high humidity or moisture, these pesky insects can be found anywhere there is plenty of water, moisture, or humidity. Including places such as rivers, ponds, creeks, or any other areas that are near a source of water.

Of course, they don't limit their favorite place to bodies of water. Fungus gnats find birdbaths and houseplants that are leaking water from other areas of attraction. These flying insects quickly become a nuisance as they continue to fly around your home and yard. Leaving you with one major question--how to get rid of fungus gnats?

How To Get Rid Of Fungus Gnats In Houseplants Soil

A bottle of hydrogen peroxide is one of the most effective to use get rid of fungus gnats in houseplant soil

The most effective method for getting rid of fungus gnats larvae is to use hydrogen peroxide. It is one of the fastest ways to kill these flying insects immediately upon contact. Stir together one part of hydrogen peroxide and four parts of water.

Use this combination to saturate the plant soil. Something else you can add to the plant soil is neem oil, use some water to dilute it, and it will kill any fungus gnats larvae.

Will treating the soil with hydrogen peroxide kill fungus gnats?

When you use a mixture of four parts water and one part hydrogen peroxide, you are forming an insecticide. It is so powerful it will eradicate your fungus gnat problem upon contact. Pour this solution on the soil surrounding your infected houseplant and watch those flying pests die.

Your plant is now a very fertile target for more gnats once the peroxide stops fizzing. Big problem: peroxide kills everything in your soil, including the good stuff. Healthy soil is a vibrant ecosystem with beneficial bacteria and microorganisms that help your plants grow.

What are Fungus Gnats?

Fungus gnats look a lot like mosquitoes; however, they do not bite. They are common indoor pests and are typically found flying around your house plants. The larvae feed on plant roots, fungi, root hairs, and other organic matter, such as compost.

You often will not recognize you have a fungus gnat infestation until you see them in a swarm. Fungus gnats are so tiny they are often mistaken to be fruit flies. However, there are key differences between the two.


The Difference: Fungus Gnats vs. Fruit Flies

The Difference: Fungus Gnats vs. Fruit Flies

The most prevalent pest of a houseplant is fungus gnats or Sciaridae spp. These flying pests are distinguishable from the Drosophila spp., or Fruit flies, because they are darker in color.

Another main difference between fungus gnats and fruit flies is the latter prefers rotting food, fruit, and poorly maintained refrigerators. While fungus gnats thrive in sewers, drains, and damp soil of houseplants.

Fruit flies don't cause much damage outdoors. More often, they infest houseplants or potted plants kept indoors or in a greenhouse.


What do fungus gnats look like?

Fungus gnats are also called sciarid flies. They are tiny flies in the house that appear like mosquitoes, with long legs and small bodies. The adult fungus gnats grow to a length of one-eighth inch. Their smoky-colored wings have a distinct pattern that is Y-shaped and a body that is grayish to black colored.

Outside compost or houseplant soil is where fungus gnats prefer to make their home due to its moist soil and warmth. You will face a new problem once these little flying pests find their inside. Freeing your houseplant's soil of these tiny fungus gnats.

Can Fungus Gnats Cause Damage?

Although adult fungus gnats do not bite humans or create lasting harm to houseplants, their mere presence is annoying. When there are large amounts of larvae present, the plant's roots can be damaged. In addition, fungus gnats larvae can stunt the growth of a plant, mainly if they attack young plants or seedlings.

Fungus gnats do not bite. However, they will lay their eggs in potting soil that is moist or damp. Lucky for homeowners, there are several natural ways to get rid of fungus gnats in your houseplant soil.

Life Cycle of Fungus Gnats

Life Cycle of Fungus Gnats

There are four stages in the life cycle of fungus gnats. Beginning with the eggs, to the larva (there are four larval instars or stages), next is the pupa, followed by adult gnats.

The tiny eggs and oblong-shaped pupae appear dampened by organic matter where larvae eat, and females lay their eggs. For approximately two weeks, the larvae feed until they pupate close to the surface of the soil within the chamber threads.

Here they remain in this pupal phase for three to seven days until finally emerging as adults. The adult fungus gnats survive for around eight days.

What do Fungus Gnat Larvae Look like?

The eggs of these tiny pests are difficult to see, often requiring the assistance of a dissecting microscope or powerful hand lens. Fungus gnat larvae appear like tiny worms that are white and have a head of shiny black. In order to survive, the larvae must feed on fungus and require a moist environment. While in the larvae stage, they will grow to about a quarter of an inch long.

Once they reach adulthood, the fungus gnats will be a brown or black hue, with a single pair of clear, delicate wings. The adult fungus gnats are usually around one-eighth of an inch long, and many mistake them for mosquitoes due to their legs which are dangling, long, and slender.

How long do Adult Fungus Gnats Live?

Fungus gnat larvae will feed for around two weeks before they pupate at the soil surface inside the thread chambers. For the next three to seven days, the gnats remain in this pupal stage. Finally, emerging as adult gnats, living for approximately eight days.

How long do fungus gnats live in soil?

A fungus gnats larvae that have just been hatched from eggs after 3 days

Fungus gnat eggs hatch and become larvae after around three days. They then begin burrowing in the soil and feeding on decaying organic matter and decaying plant material.

The larvae can also cause severe damage to developing seedlings and young plants, as their root systems haven't fully developed

The adult gnats will come out of the soil two weeks later, ready to lay eggs, and the process repeats.

In houseplants that have too much moisture in their potting soil, high populations of fungus gnat adults and larvae are associated with the death of plant matter. Before that, it's difficult to tell whether or not the issue is feeding larvae or overwatering infections by fungi, or generally unhealthy roots.


How do I Get Rid of Fungus Gnats Infestation?

One way to prevent fungus gnat infestations is by using a water level indicator or monitor found at any home and garden center. These gauges ensure you do not over or under-water plants.

Allow the top two inches of soil to dry out completely before watering again. Doing so averts a moist soil surface that will form fungus.

You might also want to cover the top of your soil with actual compost or fine sand. Fungus gnats prefer areas that are moist. Therefore, ensure planting pots have good drainage holes, only watering plants when the top one to two inches of the soil surface is dry. (Especially imperative during the winter, when houseplant growth is less).

When the soil surface is always dry, it aids in halting fungus gnats from laying their eggs in the soil.

Cultural Control of Fungus Gnats

Moist soil is where fungus gnats thrive; therefore, avert the overwatering of plants. A key strategy to managing a cultural control of fungus gnats is making certain plant roots are well drained.

Ensure the soil's top surface is completely dry prior to watering plants. Doing so will aid in killing gnat larvae and preventing future generations.

Biological Controlling Fungus Gnats

A nematode as one of the primary ways to biologically get rid of fungus gnats

There are three primary ways of biologically controlling fungus gnats. These ways include predatory anthropods, nematodes, and bacteria. Utilizing these organisms is beneficial when released into the crop cycle early on, then routinely re-introduced.

A parasitic nematode called steinernema feltiae works well because it actually attacks the larvae of fungus gnats.

Organic Fungus Gnat Control

Another method to use when you have new potting soil and want to control a fungus gnat problem is doing so organically. To do this, measure four parts of water with one part peroxide.

Pour this mixture into the potting mix and dry soil until it saturates the potting mix and soil, and you see it coming out of the base of the potting mix.

Fungus gnat larvae will be killed instantly as the peroxide comes in contact with them. Neem oil is another way to soak the soil and effectively fight off fungus gnat larvae.

How to Make a homemade gnat trap

Making your own homemade bug sprays and gnat traps may also help you to kill fungus gnats. You can use apple cider vinegar to make a homemade spray bottle and gnat trap. Fill a small, shallow container with equal parts water and apple cider vinegar.

Ensure the apple cider vinegar and water mixture is a minimum of one-fourth of an inch deep. Now, stir in a few drops of liquid dish soap and place the trap near the base of the affected plant or on top of the soil.

Fill a shallow container with 1/4 inch apple cider vinegar and a few drops of dish soap. Cover with some plastic wrap and poke a few holes in the plastic wrap. Make sure the holes are big enough for the gnats to get inside. The vinegar's scent may attract them.  A homemade apple cider vinegar trap needs to be replenished every few days so they continue to attract and kill adult gnats.

Small yellow sticky traps can be cut, placed on wooden stakes, and inserted into pots close to the soil, where mosquito larvae and adult gnats tend to crawl and fly.

What natural or organic methods can I use to get rid of fungus gnats?

A sticky organic trap as one of the natural method to get rid of fungus gnats

You can get rid of fungus gnats using natural methods by setting organic sticky traps to kill the adult fungus gnats. Do this by filling the bottom of a deep bowl with apple cider vinegar or red wine. Then add several drops, and place the bowl near the most often infested plants, potted plants.

It is best to place sticky traps around houseplants that have been infested or directly on the top of infested soil.

Next, place the bowl near the most infested plants, potted plants, or house plants. The fungus gnats will relish this sweet treat, falling into the liquid as they attempt to eat it and drown.

How to Prevent Fungus Gnats

One way to prevent fungus gnats is to check your houseplants frequently for leaking water. Doing this averts any future infestations from taking too much moisture to hold.

When it comes to long-term prevention, non-pesticidal methods are recommended to prevent the flying gnats from harming your indoor plants or the other indoor plants or animals in your home.

What causes fungus gnat infestations?

When there is plenty of moisture within a home, it will attract a fungus gnats infestation. Excessive moisture allows fungus gnats to thrive and fungi to grow.

If any appliances have malfunctioning or leaky pipes in a basement or elsewhere, fungus gnats will find it attractive.

However, the most popular reason for a fungus gnat infestation is indoor plants that have been overwatered.

Do Fungus Gnats Harm Humans?

Fungus gnats are completely harmless to humans since they can't bite and don't spread diseases. They can be a problem for houseplants. However, when their population explodes, and their larvae start to feed on plants' thin roots, they do become pests to humans.

Fungus gnats may also spread Pythium, a group of plant pathogens that causes “damping off” in seedlings.

Do Fungus Gnats Bite?

A damp potting soil where fungus gnats lay eggs

This type of gnat doesn't bite, but they do lay eggs in damp potting soil. Luckily, there are multiple natural methods how to get rid of fungus gnats in houseplants.

Fungus gnat larvae survive on damp, rich soil, feeding on plant roots and organic material, such as compost. Although their constant flying around is a nuisance, they do not spread diseases or harm humans.

How to Control a Fungus Gnat Problem

You can control fungus gnats using a soil cover over the potting soil. Fungus gnats cannot survive without oxygen. Therefore, ensure to store unused potting soil in an air-tight, sealed container. Leaving potting soil bags open can become a breeding ground for fungus gnats, so make sure you keep that in mind when storing unused soil.

You can use neem oil as a soil drench after removing the top inch of soil dry top, then replace it with a fresh dry layer or use a soil cover.

Add 1/4 inch of horticultural sand (do not use play sand) to the top of the soil in your containers to help discourage fungus gnats from laying eggs around the plants.

You can also try placing the cut side of a potato on the soil surface to draw some of the larvae out. Be sure to remove infested pieces quickly and replace them with fresh slices on a regular basis until you eliminate the problem.

Cover drainage holes with a piece of synthetic fabric to prevent the gnats from getting in or out of the holes. Ensure the water can still pass through the drainage holes freely. Though gnats typically remain near the tops of planting pots, aiding them in finding their way to the drainage holes on the underside of a pot to start laying eggs there, too.

Another way to deter fungus gnats from laying their eggs is using mosquito dunks. Simply fill a gallon jug (or watering can) with clear water and toss in the mosquito dunk.

Do not use any potting mix containing processed forest products, bark fines, or actual compost. African violets, poinsettias, geraniums, and other plants are at potential risk of injury by these small flies.

When it's Time to Call the Professionals

Best pest control services in New Lenox

When you have tried all the yellow sticky traps and your potted plant's soil dry, but you still have gnats flying around, call A.N.T. Pest Control. These small flies are often confused with being drain flies or fruit flies.

When fungus gnat larvae wreak havoc on your African violets and other beloved plants, call A.N.T. Pest Control. Call A.N.T Pest Control today at 815-215-7211 and start protecting your beloved potted plants from being harmed by these flying pests!

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