“There are numerous treatments for both ailments with many being organic but after heavy rain, it’s advisable to apply a treatment as soon as you can.”
Black spot is a serious disease for roses.
The disease is caused by fungus called diplocarpon rosae which infects the leaves and stems, making the plant unhappy.
If left, the plant’s leaves will turn yellow and drop off.
Powdery mildew on roses is a disease caused by the fungus Podosphaera pannosa.