Fungus Gnats

Fungus Gnats can easily reduce the quantity and quality of your harvest. You might have seen them moving about before when watering or moving your plants around.

Keep reading to find out how to detect, prevent and get rid of fungus gnats in cannabis plants.

What are Fungus Gnats

Fungus Gnats are also known as soil flies, fungus flies etc. There are thousands of species, although only some of them attack cannabis plants.

A certain species known as Bradysia attacks cannabis roots’ directly when in its larvae state. Scatella Stagnalis is another species that indirectly affects the plant, leaving an open gate for mould and fungus infections.

Fungus Gnats tend to act as a vector for fungi infections, especially during their larvae stage, which is when they can transmit illnesses such as Fusarium and Pythium.

How to Detect Fungus Gnats

During their adult phase they look like small flies, from 2 to 4 mm, with a lazy and slow flying pattern. They tend to be on top of the substrate, near the base of the plant.

You won’t be able to identify them based on the damage they case, as fungi and pathogen infestations can have many other causes.

How to Prevent Fungus Gnats

Preventing fungus gnats is relatively easy:

If you grow indoors make sure the humidity levels are in check.
Do not water in excess. In order to know b, lift up the one with the driest substrate and then the one with the wettest; this will allow you to learn what heavy pots and watered-down pots feel like, which makes it easier to know when to water.
Use Trichoderma in your substrate, which acts as a preventive treatment for nasty fungi infestations. You can check out our catalogue for products such as Aktrivator, Trikologic S and Bio 16 Trifag.
Place yellow and blue sticky traps in order to catch any type of flying insect such as aphids, thrips, white flies and fungus gnats.
If you’re using a homemade compost or you’re using manure, make sure that it has been fermented correctly and contains no insects.
Use neem oil dissolved in water when watering the substrate every now and then; this can help to keep fungus gnats away.

How to Get Rid of Fungus Gnats

If you’ve seen fungus gnats in your grow, don’t just stand there. They will grow in number and soon become impossible to control.

In order to get rid of fungus gnats, we recommend using products such as Spruzit, an organic product that combines pyrethrins and rapeseed oil.

In order to get your plants back to optimal health we also recommend using an anti-stress product such as Revive or Regulator.

If you grow indoors and you’ve been dealing with an infestation that’s hard to get rid of, we recommend using Solfac before starting another grow. Solfac must not be used with plants in the room; it’s designed to be used in between grows.

Before handling insecticides: