Here are two interesting articles about diseases of pelargoniums:
Geranium Diseases – Identification and Control in Landscapes and Indoor Settings
Of course, nobody wants to think about this stuff. Unless you have a greenhouse full of geraniums, why bother? The thing that really caught my attention was the emphasis on prevention. These nasty problems can be so easily prevented with good plant culture:
- Start with clean pots and clean soil
- Leave room between plants for proper air circulation
- Water the soil, not the leaves
- Water early in the day
- Remove diseased plants and plant parts quickly
- Excellent drainage
