Grey mould (botrytis)
Botrytis or Grey Mould is a very common fungal disease, causing a growth of fuzzy grey mould. It infects many plants, especially those grown under glass where conditions are humid.
Remedy: Remove dead and dying leaves, buds and flowers promptly. Do not leave dead plant material lying around. Reduce humidity by improving ventilation and do not overcrowd plants.
Cultural measures: Avoid over-watering and ensure good drainage. Avoid misting plants. Improve ventilation/ air circulation around those plant and increase plant spacing, dont over plant. Remove affected plant parts and any fallen plant debris.
There is no chemical currently on the market registered to control this problem.