We have been back almost two weeks and have barely any new fungus gnats. Which if you would of seen the amount invading our home you would be impressed. It was no fun trying to eat anything food related as they just swarmed over it. Now to get rid of fungus gnats and keep them gone you have to be diligent and not stop. You need to make sure your doing ALL the things I’ll be mentioning below for well over a month. You need to understand that a week or two of maintenance will not be long enough to hold them at bay and you will find yourself with an infestation again.
Before we hop into how to get rid of them. I want to share more about these annoying little bugs so you can be well equipped when attacking them.

How did I get Fungus Gnats?
Fungus gnats are usually brought home with a new plant or hiding away in that new bag of soil you just repotted your plants with.
Fungus gnats lay their larvae in moist soil and that larvae will then hatch about two weeks later. If during this time before they hatch the soil dries out completely then they become dormant and wait for the soil to become moist again to finish their process of become adult larvae.
The fact that they can go dormant makes it really hard to tell if a new plant is carrying them or if your bag of soil is full of them… until they soil gets watered.
How long do the adults live?
The adults live about 7-10 days and will lay hundreds of eggs in the top layer of your soil during this time.
How long do the eggs/larvae live?
The eggs take about 2 weeks to hatch and a couple more days after that to develop their wings and become adult fungus gnats.
What are they attracted to?
To lay their eggs they are attracted to moist areas with organic matter. Which makes your plants soil the perfect egg laying place for them.
They are also attracted to fermented things which is why the apple cider I’m going to mention below works.
Will they go away on their own?
No. They will keep laying eggs and keep hatching and this will repeat until they kill your plants root system.
Do I need to repot my plants?
I see a lot of people that say to just repot your plants with new soil. But you never know if your new soil has larvae in it. They are undetectable when they are dormant.
So if you use my tips below you do not need to repot or replace your soil. But if you do decide to then you need to rinse out your roots completely and it reuse the pot you or guan lay had them in until your scrub it clean. but like I said you chance missing one larvae or having more in your bag of soil.
So since you came here to find out how to get rid of or prevent them let’s get to what I do and has proven to be fully effective when all are done together.
How to get rid of them, prevent them and kill their larvae….
How to kill the adult fungus gnats?
- Apple Cider Vinegar
To kill the adults you need to create a mixture of apple cider vinegar, dawn dish soap and water. You’ll want to have enough small containers filled with the mixture places around your plants so the scent is strong enough to attract them to it.
They are attracted to things that have been fermented (that sweet but bitter smell) and apple cider vinegar is. So it will attract them. Once they are attracted to it and head down to enjoy it, your going to need something that will prevent them from flying back out. And this is where the dawn dish soap comes in. Something about it removing the waxy coating on the bugs and drying them out is what the dish soap does. But it doesn’t work alone you need to mix it with some water.

Items needed:
- Apple cider vinegar
- Dawn dish soap
- Water
So I typically poor my apple cider in first to about an inch deep. Then a drop or two of dish soap and then about a tablespoon of water. Swish it around with a fork or I I’ve to get it all mixed up and place it around your plants.
DO NOT set it on your plants soil. Vinegar can kill your plants and you don’t want it accidentally be knocked over. Instead just set it around where you notice the gnats flying.
How to kill the larvae/eggs?
- Mosquito Dunks
One of the hardest parts of stopping a fungus gnats infestation is getting rid of the eggs that are in the soil. You don’t know where they are all at and you still need to be able to water your plant… right!
That’s why I use Mosquito Dunks! They are intended for mosquito larvae but work just as good on fungus gnats also. They don’t kill adults so don’t expect it to be your cute for all. The one I use has been certified to be used with organic farming and is even safe for ponds. It’s a natural bacteria (kinda like yogurt) that isn’t harmful to animal life or your plants. It’s only harmful to flying back bugs larvae but you can’t just throw one on top of your soil or it won’t do anything. Your going to need to create a “soup” out of it.

You need to break your dunk into pieces and let it sit over night in a container of water to dissolve and then use that water to water your plants with. You’ll want to make this “soup” and water them with it for at least 6 weeks. Remember you need to be diligent to get rid of them fully.
Now because I have well water and a softener system I’m unable to use water from my house. We do have an outside water spigot that’s from a well with no water system. So I actually got a 33 gallon trash can that I fill up with it and through my dunk into that and let it sit outside for 24 hours. Then use that to water all my plants. I now let it collect rain water and just add a new mosquito dunk when one dissolved completely. Because the dunk is in the garbage can of water I don’t have to worry about it attracting mosquitos either.
How to prevent them in the first place or from coming back?
- Let your soil dry out
- Bottom water only
- Sprinkle cinnamon on your soil
Let your soil dry out:
Adult fungus gnats only lay their eggs in moist soil. So if you let your plants soil dry out between watering them they won’t have anywhere to lay their eggs and won’t be able to keep breeding.
Now I know not all plants like being completely dry so if you have a plant that doesn’t like to go to long between watering just make sure you keep the top inch or so dry at all times.
Bottom water only:
Now we all know you can’t stop watering your plants all together and done plants are thirstier than others. So to help your top inch of soil consecutively drive you will need to start bottom watering them. I personally use both self watering planters that do this and manually doing it.
To manually do it I use a couple of my baking/cookie sheets. I place all my plants that need to be watered on it first. Then add my water from mosquito dunk soup into the pan. About every 10-15 minutes I’ll check the water level. If it’s empty I’ll add more and if it hasn’t changed then I know they have gotten all they needed.

Sprinkle cinnamon on your soil:
Cinnamon is a natural way to kill fungus. When your plants soil remains wet for to long it can start to grow a fungus on top and fungus gnats absolutely love it! So once you have your top layer of soil dried out you can then sprinkle on cinnamon to kill the fungus that also helps attract them.
I hope these tips and FAQ’s helped you discover how to finally get rid of your fungus gnats and keep them gone. And if you don’t have yet but have house plants then how to prevent them in the first place. Bottom water and not over watering your plants can be your biggest preventative measure. I’ll be sharing how often to water your house plants in a blog coming soon so keep an eye out for that.
Until next time, live a life you love!
Xo Jessica!