Safe, Natural Remedies to Beat Back a Fungus Gnat Invasion

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If you have houseplants, you may have noticed tiny black bugs flying around them. These are fungus gnats, and they can be a nuisance! Not only are they annoying, but they can also damage your plants.

I've had an outbreak of these pesky pests, and they particularly liked my orchids and Philodendron micans. So, I will share several methods that have helped me get rid of fungus gnats on my houseplants and some tips on preventing them from returning.

Keep reading as I'll share more details on how to get rid of fungus gnats and prevent them from ever attacking your plants again.

What are fungus gnats?

Fungus gnats are tiny dark-coloured flying insects with long legs and are often found near sources of moisture, such as potted plants.

The larvae are white and resemble worms. Both adult gnats and larvae feed on fungi, which is why they are often found near damp areas. While they do not typically cause severe plant damage, large populations can be a nuisance.

Fungus gnats are attracted to light, so they often enter homes through open doors and windows.

How to Get Rid of Fungus Gnats on Houseplants Naturally

Fungus Gnats Development Stages:

If you're anything like me, you're fascinated by the inner workings of nature. So, let's take a closer look at the development of fungus gnats!

These tiny insects go through four stages in their lifecycle: egg, larva, pupa, and adult. The egg stage is the shortest, lasting only a few days before the larva hatches.

The larva stage is when the gnat undergoes its most dramatic transformation, growing from a tiny worm-like creature into a pupa. This process takes around two weeks.

Once the pupa has emerged from its cocoon, it moults again to reveal the adult gnat. And there you have it – the complete life cycle of a fungus gnat!

Are gnats bad for plants?

While they may seem harmless, gnats can actually be bad for plants.

They feed on plant nectar and can spread diseases from one plant to another. In addition, their larvae feed on plant roots, damaging the plant and making it more susceptible to disease.

Adult and larval stages are thought to spread disease spores during their migration, such as Fusarium, Pythium, and Thielaviopsis.

So if you see gnats around your plants, it's best to take measures to eliminate them.

How do fungus gnats get into houseplants?

Here are a few different ways fungus gnats can make their way into your home. They might hitch a ride on a new plant you bring inside, or they could come in through an open door or window.

If you suspect that you have a fungus gnat infestation, check your plants for tiny black flies. Once they're inside, they'll lay their eggs in the damp soil of your plants. The larvae will then hatch and begin feeding on plant roots, especially if they are young plants.

How to Get Rid of Fungus Gnats

Fortunately, there are a few simple steps that you can take to get rid of these pests. For example, allowing the top inch of soil to dry out between waterings can help to reduce the gnat population. In addition to the following ways to help get rid of fungus gnats.

Avoid overwatering

Make sure to keep the soil moist but not soggy. Second, water your plants from the bottom rather than from the top. This will help to prevent fungus gnats from laying their eggs in moist soil.

Bottom watering

Many people are familiar with top watering or pouring water directly onto the soil surface of houseplants. However, bottom watering is another option that can be beneficial for both plants and gardeners.

Bottom watering involves placing the plant in a container and allowing the water to soak up from the bottom. This method can help to reduce the risk of overwatering, as the plant will only absorb as much water as it needs.

In addition, bottom watering is often easier on the leaves and stem of the plant, as there is no risk of damage from heavy watering cans. As a result, bottom watering can be a convenient and effective way to keep houseplants healthy and hydrated.

Repot in fresh soil

If you've ever had the unfortunate experience of dealing with fungus gnats, you know how frustrating and persistent they can be.

One way to eliminate fungus gnats is to repot your plant in fresh soil, as they are attracted to decomposing organic material. This will help to remove the infestation and give your plant a chance to thrive. In addition, repotting will give your plant a fresh start and can help to improve its overall health.

Just be sure to dispose of the old soil properly so you don't reintroduce the fungus gnats into your home.

Bake your potting soil

As any houseplant gardener knows, the soil is essential for growing healthy plants. Not only does it provide nutrients and support for roots, but it also helps to regulate moisture levels and prevent weed growth.

However, soil can also be a breeding ground for pests like gnats. These tiny insects are a nuisance and can damage plant life.

The good news is that a simple solution is baking your potting soil. Baking your soil will help to kill any gnats that are present, as well as their eggs.

Just be sure to let the soil cool completely before using it for potting your plants. Otherwise, you might have some very unhappy (and possibly roasted) roots.

Spread the soil evenly on a baking sheet and bake at 148c (300f) for 30 minutes.

7 Ways To Get Rid Of Fungus Gnats

As previously mentioned, if you have ever seen tiny black flying bugs hovering around your indoor plants, chances are you having a run-in with fungus gnats.

Fortunately, there are a few simple ways to eliminate fungus gnats. Here are seven effective methods:

1: Hydrogen Peroxide 3%

Fungus gnats can be difficult to control because of how quickly they can reproduce, which is between 100 and 150 eggs per day, and adult fungus gnats can live about a week, so that is a possible 1050 eggs in one week per female adult, that's a whole lot of gnats!.

However, there is a simple solution that uses hydrogen peroxide and water. The hydrogen peroxide 3% will kill the larvae, and the water will help to dilute the hydrogen peroxide so it won't damage your plants.

To use this solution, mix one-part hydrogen peroxide with four parts of water and pour it over the affected area. 

2: Yellow Sticky Traps

Yellow sticky traps are a simple and effective way to eliminate fungus gnats. These traps are coated with a sticky substance that attracts and traps the gnats.

The bright yellow colour attracts fungus gnats, and the sticky surface ensures they won't be able to escape. Just place the traps near infested plants, and watch as the gnats are drawn in and trapped. With patience, you can quickly end your fungus gnat problem.

3: Natural predators

If you're looking for a safe, effective way to eliminate fungus gnats, consider using a biological control agent. Unlike chemical pesticides, biological control agents are safe for people and pets and won't harm the environment.

One type of biological control agent effective against fungus gnats is Steinernema feltiae – a parasitic nematode.

Beneficial Nematodes are microscopic worms that seek and kill insect pests like fungus gnats. When applied to the soil, they will search out and destroy fungus gnat larvae, providing long-lasting protection against these pesky pests.

4: Diatomaceous earth

Diatomaceous earth may be the answer if you struggle with a fungus gnat infestation. Diatomaceous earth is made from the fossilised remains of freshwater algae, and it's very effective at getting rid of pests.

When scattered around the base of plants, it creates a barrier that prevents fungus gnats from laying their eggs. The sharp edges of the diatomaceous earth also puncture the insects' exoskeletons, causing them to dehydrate and die.

So if you're looking for an environmentally-friendly way to get rid of fungus gnats, diatomaceous earth is worth considering.

5: Vinegar Traps

Fungus gnats are attracted to damp soil, so one way to get rid of them is to make a vinegar trap.

To do this, mix equal parts apple cider vinegar and water in a bowl and cover it with plastic wrap. Pierce a few holes in the wrap and set the bowl near your plants. The gnats will be drawn to the vinegar and drown.

You'll need to empty the bowl and refill it every few days, but eventually, you should see a decrease in the gnat population. If you're still seeing a lot of gnats, you may need to treat them with an insecticide.

However, the vinegar trap is a safe, natural way to eliminate fungus gnats.

6: Neem Oil

Neem oil is derived from the seeds of the Neem tree, and it's been used for centuries in India for its pest-repelling properties.

When applied to the soil, Neem oil creates an inhospitable environment for fungus gnats and other pests, causing them to die off before they can damage.

Mix water and Neem oil according to the bottle's directions and spray it around your plants.

Home Made Neem Oil Spray Recipe:

Be sure to spray the leaves, both top and bottom, and stems and insects. This will help eliminate the insects on contact, so you might need to reapply this solution a few times to stop all the pests.

7: Mosquito Dunks or Bits (BTI)

And my favourite way to get rid of fungus gnats is to use Mosquito bits or dunks and make a watering solution or “tea” to water your plants. I have used this with great success in getting rid of my plague of fungus gnats.

These pellets contain an active ingredient called Bacillus thuringiensis subspecies israelensis, or BTi, a naturally occurring bacterium toxic to mosquitoes.

When consumed by mosquitoes, Bti produces a toxin that causes the insect's digestive system to rupture, leading to death. While Bti is effective at killing mosquitoes, it is safe for humans and other mammals. 

mosquito bits

How to Keep Your Houseplants From Being Attacked by Fungus Gnats Again

Once you've gotten rid of your current fungus gnat problem, you'll want to take steps to prevent them from returning.

The best way to do this is to let the top layer of soil dry out between waterings. Fungus gnats thrive in damp conditions, so allowing the soil to dry out creates an inhospitable environment.

You should also avoid overwatering your indoor plants. Water only when the top of the soil is dry to the touch, and be sure to have drainage holes in your pots and empty any trays or saucers so that the bottom of your pots is not sitting in water.

Finally, make sure you're not overdoing it on fertiliser. Fungus gnat adults are attracted to the nitrogen in fertilisers, so using too much can attract them to your plants. Stick to a light feeding schedule and only fertilise when your plants are actively growing.


Why are fungus gnats attracted to my breath?

Fungus gnats are small flies that feed on fungi, algae, and decaying organic matter. They're commonly found near potted plants or in damp, humid places. The adult fungus gnats don't bite or sting, but their larvae can damage plant roots if they hatch in large numbers.

So, what attracts fungus gnats to our breath? It turns out that the carbon dioxide we exhale is a key component of our diet. We release a little cloud of food for these pests when we breathe out! Many commercial traps use CO2 to lure and kill fungus gnats.

While they're not dangerous to humans, fungus gnats can be a nuisance. But now that you know why they're attracted to your breath, maybe you won't mind sharing a little bit of air with them next time you meet! If you find them in your home or garden, there are several ways to get rid of them.

Are fruit flies the same as fungus gnats?

Are fruit flies and fungus gnats the same insect? This is a common question among many homeowners.
While they may seem similar, several key differences exist between these two types of pests. Fruit flies are attracted to overripe fruits and vegetables, while fungus gnats are attracted to damp soil.

This means that you're likely to find fruit flies in your kitchen, while fungus gnats will be more likely to show up in your bathroom or laundry room.

Additionally, fruit flies are generally much bigger than fungus gnats. Finally, fruit flies typically only live for a few days, while fungus gnats can live for up to six weeks.

So, while these two insects may share some similarities, several key differences make them easy to tell apart.

Do fungus gnats indicate root rot?

If you're like most gardeners, you probably dread seeing fungus gnats buzzing around your plants. Not only are they annoying, but they can also be a sign of root rot.

Root rot is a severe problem that can quickly kill a plant. The first step to preventing root rot is to identify the signs. Fungus gnats are one such sign.

These tiny insects feed on the fungi that grow on rotting roots. If you see fungus gnats, it's essential to check the roots of your plants for signs of decay.

Thankfully, there are several effective treatments available. If you find any, you'll need to take action to prevent the root rot from spreading.

How do you kill Fungus gnats in soil?

If you're having trouble with fungus gnats in your soil, don't fret! There are a few quick and easy solutions that can help.

Sprinkling some diatomaceous earth on the surface of the soil, followed by tilling it into the top inch, is one option – this will reduce their population.

You can also try reducing watering to keep things drier or even treat it with hydrogen peroxide mixed at a 1-3 or 1-4 ratio; be sure to wet down only about an inch of soil for this solution.

And Finally…

If you're having a problem with fungus gnats, there are several things you can do to get rid of them.

The best way to prevent them from returning is to let the top layer of soil dry out between waterings, avoid overwatering your plants, and use only light fertilising schedules.

It would be best if you also emptied any drainage trays or saucers so that the bottom of your pots isn't sitting in water.

Please see all the houseplant supplies I love and use.

image of fungus gnats stuck to a yellow sticky trap with text overlay 7 ways to get rid of fungus gnats

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