Pest & disease index
Something eating your plant? Start here. Each guide covers one pest or disease in full - how to spot it, the damage it does, and how to treat and prevent it - and lists which of our 724 profiled plants are known to get it. Not sure what you are looking at? Try the plant problem solver by symptom.
Pests
Mealybugs
Slow, soft scale insects that look like little blobs of white cotton wool tucked into leaf joints.
Spider Mites
Tiny sap-sucking mites that thrive in warm, dry air and quietly bronze a plant before you see them.
Aphids
Soft, pear-shaped sap-suckers that cluster on tender new growth and breed astonishingly fast.
Scale Insects
Sap-sucking insects that disguise themselves as small, hard brown bumps stuck along stems and leaves.
Slugs & Snails
Night-feeding molluscs that shred soft leaves and seedlings, leaving ragged holes and slime trails.
Thrips
Slender, fast-moving insects that rasp the leaf surface, leaving silvery scarring and black specks.
Fungus Gnats
Small black flies that hover around damp compost - mostly a nuisance, but a sign the soil is too wet.
Whitefly
Tiny white moth-like insects that erupt in a cloud when you brush a leaf and coat plants in honeydew.
Diseases & disorders
Root Rot
The most common houseplant killer - roots suffocating and rotting in soil that stays too wet.
Powdery Mildew
A fungal disease that dusts leaves with a white, flour-like coating, spreading in warm, still, crowded air.
Rust
A fungal disease that speckles leaf undersides with raised orange, brown or rusty pustules.
Grey Mould (Botrytis)
A fuzzy grey fungus that rots soft leaves, stems and flowers in cool, damp, still air.
Leaf Spot
Fungal or bacterial spots that mark leaves with brown or black patches, often ringed with yellow.
Damping Off
A soil fungus that topples healthy-looking seedlings overnight, collapsing them at the base.
The "X plants" count shows how many of our profiles name that problem in their own troubleshooting notes - a rough guide to how common it is, not a complete host list. For a specific plant, read its full care profile, or rescue a struggling one with the plant rescue guides.
Tools for finding and keeping pests off
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