Q How can I get rid of fungus gnats in my house-plant collection?
Leigh Greenslade, by email
A MATTHEW SAYS Fungus gnats, or sciarid fly, are a nuisance, especially when they are indoors, plaguing seed trays or house plants. They seldom cause severe damage to plants but are incredibly annoying to anyone in the house, where they seem to enjoy flying around your face, and landing in freshly poured glasses of wine!
They love fresh, damp, compost, so newly potted plants are ideal hosts. Watering your plants from the base or pouring water into a saucer or pot cover will help, as will mulching the top of the pot with grit, which makes access to the compost surface harder. But for complete control I favour a nematode drench. Buy these online, then mix in a watering can and water into your plants. The nematodes devour the fly larvae, and they will soon be gone.