How to Get Rid of Fungus Gnats in Houseplants
Every indoor jungle has its challenges, and tiny black flies hovering over pots is a common one. These are usually fungus gnats – small insects that thrive in damp soil. While adult gnats are mostly harmless, their larvae feed quietly on roots and compost, which can cause stunted growth, yellowing leaves and wilting, especially in young or weak plants.
If you’re wondering how to get rid of fungus gnats in houseplants, the key is to break their lifecycle by reducing moisture, preventing egg-laying and controlling adult flies.
Left unchecked, they can turn a collection of greenery into a serious source of frustration for any plant parent. Here are a few simple steps that can make all the difference.
Spot the signs
Fungus gnats are tiny, dark flies that tend to stay close to the soil. You might notice adults hovering near pots or tiny, worm-like larvae in the top layer of compost. Plants can show subtle signs of stress too – slower growth, yellowing leaves or delicate roots may indicate larvae are present. Catching the problem early makes it much easier to prevent it from spreading.
Adjust your watering routine
These pests love damp soil, so one of the simplest ways to break their lifecycle is by letting the top layer of compost dry out between waterings. Most houseplants drink less during cooler months, so now is a good time to check soil moisture before reaching for the watering can. A handy tip is the pencil trick – simply stick a clean pencil (or your finger!) into the compost. If the top couple of inches are dry, it’s time to water. While you’re at it, gently aerate the soil to help water reach the roots evenly, encouraging strong, healthy growth.
Create a protective layer
A decorative mulch of gravel, grit or pebbles doesn’t just look stylish – it also helps stop adult gnats from laying eggs in the soil. This simple barrier, combined with careful watering, interrupts the gnat lifecycle and keeps compost healthier for longer. Using store-bought compost rather than garden soil also reduces the risk of introducing larvae indoors.
Catch and control
“Sticky traps are a simple, chemical-free way to manage adult gnats. Baby Bio® Houseplant Fly Traps naturally attract flying insects – thanks to their bright yellow colour – reducing population and helping prevent further breeding. For best results, place traps near soil level and replace them once they are full. These simple yet effective sticky sheets also work as a preventative measure, helping to stop infestations in their tracks when combined with your regular watering and feeding routines.”
For serious infestations
Sometimes, despite your best efforts, gnats can take hold and become difficult to manage! In these cases, a quick spray of Baby Bio® Houseplant Bug Killer Ultra can help regain control, giving visible results within just 24 hours and offering up to eight weeks of protection. Simply spritz problem plants generously – including the undersides of leaves – and allow it to work its magic.
Feed for resilience
Healthy plants are less susceptible to pests and recover more quickly from minor damage. Regular feeding with Baby Bio® Houseplant Food strengthens roots and foliage, while a quick spritz of Baby Bio® Houseplant Feed & Mist gives an instant boost of hydration and nutrients. Strong, well-nourished plants are better able to tolerate the occasional larvae, keeping your indoor jungle looking lush and vibrant.
With a few simple adjustments, careful feeding and a little attention to watering, fungus gnats don’t have to get the better of your houseplants. Spot them early, strengthen your plants and your indoor jungle will stay healthy, vibrant and ready to flourish all year round.
