The Pesky Fliers - Fungus Gnats
By Maddy Hogan
You know those tiny pesky insects that fly right into your face when you are near a screen that appear to become more common in the cooler winter months? Those small dark gnats are fungus gnats and they are often living and breeding in your indoor plants soil. In comparison to other indoor plant pests, fungus gnats are more annoying than physically damaging to your plants and are relatively easy to combat or eradicate.
Fungus gnats get their name because they are feeding on the fungus in your indoor houseplants. Fungus in the soil is very common, especially when using a nutrient dense soil that provides many benefits to your plants. Adult fungus gnats lay their eggs in the top inch of damp soil when the larva matures. If you find a few pesky black adult fungus gnats swarming, check any houseplants with damp soil or excess moisture for a larva, silvery crawlers in your soil. Again, even the larva will not be harmful to your houseplants, however your adult fungus gnat population will quickly increase.
There are lots of solutions to prevent and combat fungus gnats that are safe for your houseplants. When you notice adult fungus gnats, it is important to identify which houseplant has the larva. Winter months are more common because it takes plant soil longer to dry out completely, leading to growth of fungus. If repotting your plant is not an immediate option, it is best to let the soil of your plant dry out completely. Once the plant soil is dry, sprinkle mosquito bits on top of the soil layer and water over them to activate. The mosquito bits will kill the fungus gnat larvae and continue to do so with each watering. We sell mosquito bits online and in our retail shop and when you purchase our repotting service, we include mosquito bits in the soil to help with the prevention of fungus gnats. Another prevention method is to put potting sand on top of your soil as adult fungus gnats cannot penetrate potting sand to lay their eggs.
In order to catch the adult fungus gnats, there are a handful of options depending on the severity of your infestation. Sticky traps are highly effective and are easily stuck into the soil to immediately begin catching the adults. Again, depending on the severity of your infestation, you will want to change out the sticky traps every few days or weekly to make sure you continue to catch the adult fungus gnats. A second option is to put out a small dish or bowl with a dish soap and water mixture to trap any flying gnats and refresh weekly. Finally, and the option we have many of at the Riza shop because fungus gnats are common and a large part of plant parenthood, are the Katchy Indoor Insect Traps. These are quiet fans that suck the fungus gnats out of the air and draw them towards an internal sticky trap, instead of staking them visibly in your plants soil.
