Famous Disease In Roses In Garden References. If you grow roses, you’ll see black spot. Flpa/alamy stock photo) rust is a fungal disease that causes orange and black blemishes on the underside of the leaves and stems of roses.
Black spot disease this very common and serious disease, caused by a fungus ( diplocarpon rosae ), is very easy to. Powdery mildew here’s another widespread rose problem that is aptly named. Weather can also play havoc on some roses, mainly by creating balling (unopened brown buds) in wet summers and powdery mildew in dry summers.
