Roses in Trouble

Asked July 24, 2018, 2:21 PM EDT

Hi, we have a beautiful hedge of rose bushes that have been with our historic house for a long, long time (looking back at old photos) One plant seemed to die off, from one lateral side of the plant to the other. I tried prunning the damaged limbs, but we eventually had to cut her down:/ Now the rose bush next in line is showing the same symtoms! Any suggestions??? I've found vidoes explaining what this may be,but nothing about how to stop it:/ Any feedback would be appreciated!

New Castle County Delaware flowers roses flower

4 Responses

Hello and thank you for contacting Ask An Expert. You mention symptoms but you did not list what the symptoms are. The only thing you did describe is that whatever affected the rose bush moved "from one lateral side of the plant to the other."
If you could reply with a list of symptoms we might be able to help you. Pictures would be great as well. You could bring a sample of the diseased portion of the plant into our office and our diagnostics lab might be able to help you with determining what might be affecting the bush. We are located at:
461 Wyoming Road
Newark, DE 19716

To submit a sample please follow the instructions for submitting a sample - they can be found at this link:
http://extension.udel.edu/ag/plant-diseases/ud-plant-diagnostic-clinic/how-to-submit-a-sample/

Hope this information has helped you. Please feel free to send a response if you have questions about submitting a sample or if you can give us more details about the symptoms.
Thanks again,
J.W.Wistermayer
UD NCC Master Gardener

thank you so much! Ok, it seems to travel from one side of the plant to the other, with the leaves looking like the attached file. I've tried pruning off the affected limbs, but we have had to cut down one bush so far, it is now onto the bush that was directly next to the one cut down.

Hello and thanks for the pictures. It appears to be "black spot." It is caused by the fungus Diplocarpon rosae. The Missouri Botanical Garden has an excellent web page with a lot of information about treating black spot - you can find the information here: http://www.missouribotanicalgarden.org/gardens-gardening/your-garden/help-for-the-home-gardener/advi...

If you do need further advice as to treatment or if you would like a diagnostic test to confirm our analysis please feel free to bring a sample into our office:


461 Wyoming Road
Newark, DE 19716

To submit a sample please follow the instructions for submitting a sample - they can be found at this link:
http://extension.udel.edu/ag/plant-diseases/ud-plant-diagnostic-clinic/how-to-submit-a-sample/

Hope this information helps!

Good luck and please feel free to contact us if you need further assistance.

J.W. Wistermayer

UD NCC Master Gardener


Thank you so much!