FUNGUS GNATS ON INDOOR PLANTS

Often, the first time you notice these mosquito-like insects is when they fly around indoors, especially when they land on light-coloured walls. Although the adult flies are annoying, they aren’t particularly damaging, and many can be caught on sticky yellow traps. The concern is the thin maggot-like larvae that eat root hairs and weaken plants.

Now that it’s warmer, take infested plants outside into a shaded spot and let the mix (and the maggots) dry out completely. Next, take the plants out of their pots, shake off all the mix and re-pot into fresh mix that’s a blend of three parts regular potting mix and one part perlite or vermiculite. This reduces the proportion of organic matter in the mix – the organic material attracts the gnats. Keep the re-potted plants outside until you think the gnats have all gone. Let the mix dry out between waterings.