Visual Guide
Fungus Gnats.
Let the top 2–3 cm of substrate dry out completely between waterings
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Photo
PhotoPests
Small dark flies whose larvae feed on plant roots and organic matter in the growing medium. They thrive in moist conditions and can cause root damage and stunted growth.
Looks like this
- Tiny black flies hovering around the base of plants
- Yellowing leaves and stunted growth in seedlings
- Visible larvae in the top layer of the growing medium
Solve it with Vitaponix
Our nutrients don't kill pests or mould — they keep plants strong while you follow the fix below.
How to fix it
- Let the top 2–3 cm of substrate dry out completely between waterings
- Apply yellow sticky traps to catch adult flies
- Drench the medium with a Bacillus thuringiensis israelensis (BTI) solution to kill larvae
Why it happens
- Persistently wet topsoil or substrate
- Decaying organic matter in the medium
- Poor airflow around the plant base
Prevent it
- Water from below or only when the medium is dry
- Cover the substrate with a thin layer of sand or perlite
- Maintain good airflow with oscillating fans
Doses and targets come from the official Vitaponix feeding chart. Vitaponix nutrients are plant nutrition, not pesticides or fungicides.