Begonia 'Cracklin' Rosie' problems — and how to fix them

White powdery patches on leaves, favoured by cool, humid, still air. Improve airflow, avoid wetting foliage, remove affected leaves, and treat with a suitable fungicide if it spreads.

Grey, fuzzy mouldy blotches in cool, wet, crowded conditions. Cut out affected tissue, reduce humidity, space plants out, and increase air circulation.

Caused by overwatering or compacted, soggy soil. Leaves go pale and droopy. Use a fast-draining mix, let the top inch dry between waterings, and ensure the pot drains freely.

White cottony masses tucked in leaf joints and stems. Dab with a cotton swab dipped in rubbing alcohol or treat with insecticidal soap or a systemic; check new growth regularly.

Insufficient light makes canes elongate with sparse foliage. Move to brighter indirect light and pinch growing tips to encourage a bushier habit.

Brown, dry leaf margins signal air that is too dry or too hot. Raise humidity, keep it away from radiators and cold drafts, and maintain steady watering.