Disease on Grandiflora Rose--Queen Elizabeth

Asked June 7, 2018, 3:55 PM EDT

I have had a Grandiflora for many rose but it has a yellow disease, mostly on the edges of the leaves. It comes back every year with the same disease covering most of the plant. The flower itself is not affected. I am thinking of digging up the rose bush and replacing it with another variety. Should I dig out the old soil where the plant was and amend the dirt and hole where the diseased rose was. The disease was also spreading to nearby roses. This queen Elizabeth is located in the center of my rose bed so I am thinking not to plant another rose which is too tall. I am thinking of a white variety since I don't have any roses that are white HYBRID TEA.

Baltimore County Maryland

1 Response

This may be black spot, which turns rose leaves yellow and then the leaves fall. Though black spot is a fungal disease that starts with a black spot of infection and then turns yellow, depending on the variety of rose shrub, the spot may not be as obvious as the yellowing.

Please read through this: https://extension.umd.edu/hgic/black-spot-roses-shrubs
In order to give you a better diagnosis, photos would be very helpful, of the entire shrub and close-ups of the leaves.

At any rate, your rose is highly susceptible to a disease, and unless you want to treat it with sprays continually, we'd recommend replacing it with a high disease resistant plant.