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How to Get Rid of Fungus Gnats

fungus gnat pest controlWhen it comes to fungus gnats, they are annoying no matter where they end up. The chances of you running into a fungus gnat issue outdoors are pretty slim, as it is more commonly an indoor issue.

Signs of Fungus Gnats

While fungus gnats are most well known for their annoyance in the garden, there are far worse things these little guys can do to your crop. To start, these little guys will slowly destroy the root zone of your plants, especially with the larvae laid in the soil. At first, you may notice the plant’s growth slowing down or leaves having issues. If not taken care of, you could even lose a plant or two.

Moreover, fungus gnats are capable of carrying other diseases, which could end up doing even more harm to your plants. One disease, in particular, they are known for carrying is pythium. This disease is primarily known to cause root rot within cannabis plants.

Getting Rid of Fungus Gnats

To start, the easiest way to prevent fungus gnats in your grow area is to prevent it from the start. First, never ever overwater your plants. If you do, you’re essentially leaving the perfect breeding ground for fungus gnats to form. Moreover, keep a clean grow area with no standing water anywhere nearby.

If fungus gnats have already become an issue in your garden, there are a couple of things you will need to do. First, you must remember that you will need to get rid of the adult fungus gnats, as well as the larvae within the soil.

Fly Traps

To do so, you can set yellow sticky fly traps, which will help to quickly get rid of the adult fungus gnats. At the same time, you will want to treat your soil, so the larvae within cannot hatch and start the breeding cycle over again.

GrowStone Gnat Nix

Personally, we love GrowStone’s Gnat Nix. By simply adding a thick layer of their recycled glass mixture to the top of your pots and/or beds, you trap the larvae in and keep the adult gnats out. Since the adult gnats cannot get into the moist soil to breed and the larvae cannot get out upon hatching, you end the life cycle of fungus gnats in your grow area.

Vinegar Mixture

Vinegar is pretty handy in the garden when it comes to getting rid of pests. Just fill a bowl with vinegar, soap, and water and set near the affected pots. Within a few days, you will notice many of the curious little critters have dove head first into the bowl, unable to get out.

Using Beneficial Insects to Control Fungus Gnats

Rove Beetles

When the infestation has reached a whole new level, purchasing some beneficial insects to chow down on the fungus gnats may be your only hope. The rove beetle can be let out in an indoor grow to get rid of your fungus gnat problem. These little guys will feed on the larvae within the soil while leaving your plants to thrive.

If you choose to use the rove beetles, you will not need other beneficial insects. The beetle will likely eat them too. Moreover, you only need a few for a small indoor grow.

Beneficial Nematodes

Another beneficial insect that works well in getting rid of fungus gnats is beneficial nematodes. Just as the rove beetle, the nematodes will feed on the larvae within the soil. Therefore, ending the life cycle of the fungus gnats in your garden.

Hypoaspis Miles

Lastly, you may choose to release the hypoaspis miles into your indoor garden to control your fungus gnat problems. These are one of the few insects the rove beetle will not eat.

Additionally, they are seen to be most beneficial when applied to soil prior to fungus gnats becoming well established. Since these mites will feed on the larvae, if already in place, you can expect your fungus gnat problem to stop likely before you ever see a hatched larvae.

Overall, by keeping proper conditions and temperatures, as well as avoiding too much water, you can prevent fungus gnats. Another great preventative measure is ensuring good soil drainage. This way if you do overwater, it can quickly drain and not leave the optimal breeding ground for longer than needed.