How to Get Rid of Fungus Gnats — Complete Guide

Complete guide to eliminating fungus gnats from houseplants. Prevention, treatment, and long-term solutions. This guide covers everything you need to know about this topic, including common causes, step-by-step solutions, and answers to frequently asked questions.

Here are the key things to understand: Cause: Overwatering — larvae live in moist top soil. Adults: Tiny black flies around plants — harmless but annoying. Larvae: In top 2 inches of soil — these damage roots. Treatment: Let soil dry + sticky traps + BTi. Understanding these fundamentals will help you diagnose and resolve this issue more effectively.

The most common reasons this occurs include: Overwatering creates perfect breeding conditions. Organic soil and peat hold moisture that gnats love. New plants from nurseries often bring gnats. Larvae feed on roots and organic matter in soil. Identifying the root cause is the first step toward finding the right solution.

To resolve this, follow these recommended steps: Let top 2 inches of soil dry completely between waterings. Place yellow sticky traps near affected plants. Use Mosquito Bits (BTi) — sprinkle on soil or soak in water. Top-dress soil with sand or perlite to prevent egg-laying. For severe cases: repot with fresh dry soil. If these steps do not resolve the issue, consider consulting additional resources or a qualified professional.

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