We know you hate them, and they are arguably most annoying houseplant pest that is completely unwelcome however everyone gets them. They look like fruit flies but instead of eating fruit, they are in your soil. Generally, fungus gnats don't always harm plants, but they can accidentally munch on plant roots in search of fungus. However whilst they don’t harm our plants, they multiply quickly and no one wants hundreds of tiny flies in their home.

 

Treatment

Gnats come out of the soil as soon as you water the soil. Just like you they don't want to drown (funny that), so they all fly to the surface and fly around.

Let’s get down to business:

1. Let your soil dry completely. Fungus grow in moist conditions and, once they do, they'll find a way into your plant's home. So, if you notice your soil staying wet for over a week, move it to brighter, dryer conditions for a bit.
2. Try Neem oil. Neem oil is also an effective to remove gnats by drenching the soil to combat fungus gnat larvae. Remember to Dilute the oil with water per manufacturer's directions. This solution is gentle on the roots, so it won't harm your plants. Only do this when the plant is ready for a watering—otherwise you're putting it at risk for root rot.
3. Try diatomaceous earth. A quick google and this stuff is the definition of death by a thousand cuts for bugs of course. Add a layer of diatomaceous earth to the top of your soil, it will literally kill them on impact!! (This is a food grade product and is totally harmless to pets and humans of all ages, some people even eat it)
4. Try neem granules. Neem granules are both natural bio-product and eco-friendly. They can be used as a soil conditioner to help restore lifeless plants and help with gnats. Neem Granules are not registered in Australia as an insecticide. However, Neem Granules have been used as a natural insecticide for thousands of years. This is a natural and organic product that prevents and kills nasty insects like gnats and mealy bugs.
5. Sticky traps. Adding sticky fly traps in and around your pot will do the trick to catch any gnat flying around. Inspect your plant frequently similar to having pets and fleas you need check on your plants and think about prevention

Prevention

Now that have treated your plants for gnats and hopefully one won, you're likely wondering how to stop it from ever happening again. Here's what you can do:

1. Check your plants. Anytime you get a new plant, it is a great idea to bath in neem oil, diatomaceous earth or neem granules to the soil. Whilst nurseries and growers try their best to manage pest control, but it's nature and it happens.
2. Prevent fungus. Try a natural fungicide such as cinnamon, water occasionally with cooled chamomile tea. When using cinnamon add a thin layer of ground cinnamon to the toil layer of the soil.