The infestation of fungus gnats in your garden or home is one of the most irritating and frustrating problems you have to deal with in a responsible manner.
Belonging to the Sciaridae family, fungus gnats are tiny, black flies often found hovering over the pots of houseplants.
Problems with fungus gnats are not restricted to your garden.
If you bring a plant infested with fungus gnats to your indoor garden, your house will be at risk of facing the irritating infestation.
What Are Fungus Gnats?
Both adult fungus gnats and the larvae are quite detrimental to your home garden as they destroy the plants very quickly if you leave them untreated.
It is through the larvae of fungus gnats the pest wreak havoc.
Adult fungus gnats lay eggs in your growing medium.
Once fungus gnats hatch, the larvae will get attached to your plant roots and deprive them of nutrients.
If you have any decaying organic material (dead leaves) in your houseplant, adult gnats will find it and get attached to it.
The adult fungus gnats choose moist soil for egg laying.
They also look for moist organic matter such as peat moss, wood chips, and compost for laying eggs.
This is why it is crucial to ensure you haven’t overwatered the plant.
What Damage Do Fungus Gnats Cause?
Since the larvae will deprive your plant roots of its nutrients, your plants will possibly die.
Adult fungus gnats carry deadly fungus diseases which can have a negative effect on your health as well.
How To Control The Fungus Gnats Pest
Keeping in view the damage these creepy, little buggers cause to your plants, it is crucial for you to learn some tried-and-tested methods to get rid of the fungus gnats infestation.
Here is what to do to get rid of this most common indoor plant pest.
Even though some argue it is more difficult to get rid of and infestation of fungus gnats than the fruit flies infestation, from natural ingredients such as neem oil and apple cider vinegar to DIY vinegar traps, there are many effective ways to control the infestation.
You don’t need a green thumb to effectively control the gnat infestations.
#1 – Drying Out Soil
- Many fungus gnats infestation happens due to too much soil moisture and overwatering of plants.
- Keep the plant-soil dry by waiting longer between watering sessions.
- This will make the soil inhospitable to gnats.
- All you have to do is to turn up around 2cms of soil in the plant.
- Doing this will expose the eggs and the larvae and will dry out the soil instantly.
- Don’t start watering the plant unless the soil has dried to a depth of at least about an inch.
- Even though this method reduces the number of larvae, but it also doesn’t eliminate the problem completely.
- This is because many plants can’t be underwatered for a long time.
- Once you start watering the plant normally, the gnats will come back again.
#2 – Sticky Traps
Another easy method to get rid of fungus gnats is by using or creating sticky traps.
Either purchase yellow sticky traps, which are made of non-toxic material and control pests in an eco-friendly and economical manner, or create your own yellow sticky traps.
This is done by smearing Vaseline on a 4″ x 6″ inch cardboard.
Then, on the top surface of the potting media, place the card horizontally to enable it to catch the adult insects as they jump from the potting soil.
In the same manner, insert a yellow trap vertically to catch the incoming whiteflies and gnats.
#3 – Food Grade Diatomaceous Earth
Another method to get rid of the fungus gnat infestation is through food grade diatomaceous earth.
This mineralized food dust contains shards of silica that shred any insect which flies through them.
If you mix the dust at the top of the soil or into your potting mix, the dust will even kill the larvae of fungus gnats which come in contact whit it.
When working with DE, it is recommended you wear a dust mask.
This is because inhaling the dust could be detrimental to your health.
Related: Tips On Getting Rid of Flies in Potted Plants | Hydrogen Peroxide for Fungus Gnats
#4 – Biological Controls
Here are some of the most common and effective biological controls for fungus gnat control.
Hydrogen Peroxide
- In a bowl, prepare a solution of hydrogen peroxide by mixing 3% hydrogen peroxide with four parts water.
- Keep the hydrogen peroxide solution aside and allow the top layer of soil to dry completely.
- Once done, spray the solution on the plants the same manner in which you water the plant.
- During the application, you will notice the soil has fizzed.
- This is a very normal reaction.
- The method of peroxide drench is a simple yet effective way to get rid of adult fungus gnats.
- You will find the solution on Amazon and use it to get rid of the infestations of fungus gnats.
Related: Home Remedy for Fungus Gnats
Chamomile Tea
Another effective treatment of killing adult fungus gnats is by sprinkling weak chamomile tea on the plants.
Brew a quart of tea and then add it to 1-gallon watering can.
Use the mixture whenever you are watering the plant.
Sprinkle it on the surface of the soil to kill the larvae and disrupting the lifecycle.
Control Fungus Gnats, Cinnamon A Natural Option
- A common and easily available natural fungicide, cinnamon powder is very effective when it comes to curbing fungus gnats.
- Effective against damping off, cinnamon powder destroys the fungus on which the larvae feed.
- The method of using the cinnamon powder is very simple, all you have to do is sprinkle enough cinnamon across the top layer of soil.
- This antifungal material is an effective way of eating the fungus you will normally find in decaying plant matter and potting soil.
Bacillus thuringiensis var israelensis
Often referred to as Bti bacillus thuringiensis var israelensis is a naturally occurring bacteria-killing different types of worms, insects, and larvae. For more on Bti check out our article on using Mosquito Dunks for fungus gnats.
The specific strains of Bt, H-14 or israelensis effectively kill fungus gnat larvae.
Beneficial Nematodes
Steinernema feltiae is the type of beneficial nematodes which is used to kill the fungus gnat.
These worm-like creatures first enter the larvae and then release a bacterium which proves to be quite lethal.
Raw Potato
Dice the raw potato into big blocks and bury them just beneath the soil surface.
Wait for four to eight hours and then pull out the chunks of the potato.
If the infestation is heavy you will see the flies crawling on the potato.