Rose black spot
Rose back spot is a fungus that affects rose plants.
As the name suggests, the disease creates black spots on the leaves of the rose plant. If the plant is very badly affected, the leaves will look fully black.
How It Is Transmitted: The fungus thrives in wet and windy conditions.
Symptoms: Purple or black spots appear on the leaves; leaves may turn yellow and then drop off. The rate at which the plant can photosynthesise is greatly affected and the plant does not thrive.
Cause: fungus
Treatment/Prevention: Spray the plant with an insecticide and fungicide.