Botrytis is a very common fungal disease found among a wide variety of plants which tends to attack wounded plants but can also affect healthy plants in humid conditions. It is common all year round and can quickly destroy a healthy garden due to it's ability to spread fast.
Fuzzy grey mould or water-soaked spots on a plant that will change colour from white, to grey and lastly brown.
Environmental conditions like low temperatures, high humidity and hard-handling of plants are all condusive to it's growth. The wetter your plants are, the more susceptible they are to becoming infected. Furthermore, standing water on plant leaf surfaces provides the ideal place for spores to germinate.
Fuzzy grey mould or growth on plant parts
Spotting, discolouration and wilting of flowers.
Brown lesions and masses of gray spores are visible on leaves and shoots
Gray mold is often found near the soil surface or in the densest areas of the plant canopy.
Flower buds may fail to open
Remove infected plants and destroy them. Prune or stake plants to improve air circulation between plant. Removed infected sections and destroy it. Treat with a biological fungicide.
Botrytis overwinters on plants, in or on the soil, and as sclerotia. Spores develop when conditions are optimal, and are moved by wind or splashing water onto blossoms or young leaves, where they germinate and enter the plant. Cool temperatures and high humidity are required for spores to germinate and spores will rarely penetrate healthy tissue directly. They prefer to enter through damaged areas, wounds or even cuttings.
Prevention is the best approach as this is such a prevalent fungus, and prevention starts with controlling your environment. Handle plants with care and make sure not to damage them. Ensure good air circulation by allowing enough space between plants and thinning out vegetation for adequate air flow. Avoid overhead-watering, overwatering and watering late in the afternoon. Good hygiene and sanitation in the garden is very important and enforce this by removing any dead leaves and debris and by sterilising your equipment often.