Pests
What to look for and what to do — Tiny flies, sticky leaves, strange speckling — most pest problems are fixable if you catch them early. A straight guide to the common ones.
Fungus gnats
Tiny flies hovering around the soil are almost always fungus gnats. They're annoying rather than dangerous to a healthy plant — the larvae live in the top layer of damp compost and feed on organic matter, only causing harm if the population gets very large.
The fix is simple: let the top inch of soil dry out completely between waterings. Sticky yellow traps catch adults. For persistent problems, a neem oil drench or beneficial nematodes (available from garden centres) deal with the larvae.
Spider mites
Fine webbing on stems and leaves, often with tiny speckles on the leaf surface where the mites have been feeding. Spider mites thrive in warm, dry rooms and can spread fast.
Isolate the plant immediately. Wipe leaves with a damp cloth to remove as many mites as possible, then spray thoroughly — undersides of leaves included — with diluted neem oil or insecticidal soap. Repeat weekly for a month. Boosting humidity around the plant discourages them from returning.
Mealybugs
White fluffy blobs tucked into the joints of stems or leaf axils, sometimes on roots. They look almost like small pieces of cotton wool. They spread fast and are worth dealing with promptly.
Remove as many as you can manually with a cotton bud dipped in rubbing alcohol, then treat with insecticidal soap or neem. Isolate the plant and check it weekly — mealybugs hide well and will take several treatment rounds to clear completely.
Scale
Small brown or tan bumps adhered to stems and the undersides of leaves. They're easy to mistake for part of the plant until you try to scrape one off.
Remove them manually with a soft brush or fingernail, then treat the area with rubbing alcohol on a cotton bud. For a heavy infestation, a systemic insecticide may be needed. Check neighbouring plants straight away — scale spreads slowly but steadily.