Troubleshooting
Pine-scented Pelargonium problems — and how to fix them
Pine-scented Pelargonium (Pelargonium denticulatum) is generally forgiving once you match its basics, but a few issues come up again and again. Here is what each one looks like, why it happens, and the fix.
Botrytis (grey mould) in cut foliage
The densely divided, sticky leaves trap fungal spores and moisture, leading to grey mould patches, especially in cool, humid or crowded conditions. Improve air circulation, remove any damaged foliage promptly, and avoid overhead watering.
Pelargonium rust
Brown pustule rings on leaf undersides; worse in humid summers or indoor overwintering conditions. Strip affected leaves, move to a more ventilated spot, and apply a copper-based fungicide if the outbreak is severe.
Whitefly
Colonies of whitefly cluster on the undersides of the sticky leaves and are difficult to remove once established. Yellow sticky traps, regular inspection, and insecticidal soap sprays help manage populations under glass.
Prevent pine-scented pelargonium problems before they start
Most pine-scented pelargonium issues are care-mismatch, not bad luck. Dial in the basics:
Pine-scented Pelargonium problems — FAQ
Why is my pine-scented pelargonium botrytis (grey mould) in cut foliage?
The densely divided, sticky leaves trap fungal spores and moisture, leading to grey mould patches, especially in cool, humid or crowded conditions. Improve air circulation, remove any damaged foliage promptly, and avoid overhead watering.
Why is my pine-scented pelargonium pelargonium rust?
Brown pustule rings on leaf undersides; worse in humid summers or indoor overwintering conditions. Strip affected leaves, move to a more ventilated spot, and apply a copper-based fungicide if the outbreak is severe.
Why is my pine-scented pelargonium whitefly?
Colonies of whitefly cluster on the undersides of the sticky leaves and are difficult to remove once established. Yellow sticky traps, regular inspection, and insecticidal soap sprays help manage populations under glass.