Begonia dregei · Perennial
Powdery mildew: Improve air circulation and apply a suitable fungicide if infection is severe.
Phytophthora root rot: Ensure well-drained compost and avoid overwatering to prevent soil-borne infection.
Fungal leaf spots: Remove affected leaves immediately and avoid wetting the foliage when watering.
Damping off: Use sterile, well-drained compost and ensure good ventilation during propagation.
Vine weevil: Apply a systemic insecticide to the compost or use biological nematodes in late summer.