Botrytis Blight (Gray Mold)
Botrytis cinerea
A very common fungal disease affecting a wide range of plants, particularly in cool, humid conditions. It causes a characteristic fuzzy gray mold.
Symptoms
- Brown, water-soaked spots on flowers, leaves, and stems.
- A fuzzy gray or brownish mold growth over affected areas.
- Flowers and buds may fail to open and rot.
- Cankers can form on stems, girdling and killing them.
Causes
- High humidity and poor air circulation.
- Fungus is widespread and can survive on dead plant tissue.
- Cool to moderate temperatures favor its growth.
- Wounded plant tissue is highly susceptible.
Prevention
- Clean up and remove dead or decaying plant material.
- Improve air circulation by spacing plants properly.
- Avoid overhead watering and keep foliage dry.
- Handle plants carefully to avoid wounding.
Treatments
- Prune out and destroy infected plant parts immediately.
- Reduce humidity and increase air flow.
- Fungicides can be used as a preventative measure, but sanitation is key.