Eliminating Fungus Gnats

Let’s talk about gnats. If you have more than just a few houseplants you have probably experienced gnats in your home. We all know just how annoying they can be so I will skip to how to control them. 

First it is important to know that fungus gnats do not bite and will not harm humans, however they can be harmful to your plants by eating the roots. We always recommend an approach using several methods at one time so that you catch the majority of the gnats and also kill their larvae in the soil as well. Here are the methods to choose from…

  1. Letting your plants dry out - Fungus gnats look for moist soil to lay eggs, so make sure you are drying out your soil as much as possible so that they are less likely to lay eggs in your soil. 
  2. BTI - BTI stands for Baccillus Thuringiensis Subspeecies Israelensis. It is “A naturally occurring, spore-forming bacterium produced commercially by fermentation.” BTI’s will kill fungus gnats in their larvae state. Our favorite BTI product is Mosquito Bits. To eliminate the larvae you are to spread the bits over the soil and when you water your plants BTI will be released into your soil. The one small downside to Mosquito Bits is that they look a little strange sitting on top of your soil so we recommend removing the top layer of soil, sprinkling the bits, and then covering them up with a fresh layer of soil just before watering time. BTI has “no toxicity to people.” Click HERE to purchase on Amazon.
  3. Yellow Sticky Traps - Fungus gnats are attracted to the yellow sticky traps and… get stuck. This is a great way to catch many adults, and is our favorite method because it’s easy to use and can sit close to the affected pot where the fungus gnats hang out. If you start treating before the gnats spread too much, this method will usually keep them under control. If you are desperate for something that will work RIGHT NOW, try taping a neon yellow notecard to a pen or pencil with vaseline spread on top of the notecard and the pen stuck into the soil. Click HERE to purchase sticky traps on Amazon.
  4. Apple Cider Vinegar + Dish Soap + Water - You can also set traps with a mix of these three products likely found in your home. The apple cider vinegar attracts the gnats, the dish soap cuts surface tension to make them fall under, and the water boosts your product to make it stretch further. The ratio does not have to be exact, but something close to a 1:1 ratio of apple cider vinegar and water, and just a drop of dish soap. If you do not have apple cider vinegar, any sugary juice will work.
  5. Diatomaceous earth - This natural product sounds a little brutal when you know how it works. “Diatomaceous earth is made from the fossilized remains of tiny, aquatic organisms called diatoms” and it works by cutting up anything that touches it. It will work for both stages as the adults will come into contact with it when they land to lay eggs, and the larvae as they crawl out to fly away. It will also act as a preventative for the adults because it will be a dry powder and not a likely place for them to want to lay eggs. Click HERE to purchase on Amazon.
  6. Sand - a layer of sand over the top of your soil can discourage gnats from laying eggs in your soil as it is dry and isn’t a medium they would like to eat. Click HERE to purchase on Amazon.
  7. Insecticidal Soap or Neem Oil - either product can be used as a spray for the adults. If you get too close to the soil the adults will fly out so be very still as you get close and quickly drench the soil in mist to catch the adults. Click HERE to purchase Insecticidal Soap and HERE to purchase Neem Oil on Amazon. 

To prevent the spread of any pest it is wise to quarantine your new houseplants by themselves for a little while to identify any pests before introducing them into the rest of your home. If you do notice fungus gnats, do not lose faith in the shop from which you purchased your plant. Like most pests, they may not be visible to the eye until larvae in the soil hatch, which usually originates while plants are growing in nursery environments or greenhouses.

It is possible to get rid of fungus gnats and have them stop flying in your face! We hope this article is helpful in your fight and would love to hear any feedback. 

Sources:

https://www.epa.gov/mosquitocontrol/bti-mosquito-control

https://www.summitchemical.com/mosquito/mosquito-bits/

http://ipm.ucanr.edu/PMG/PESTNOTES/pn7448.html

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