I'm afraid I have canes similar to that, and I'm not sure whether it's rose canker, rose mosaic disease or something else. However, the roses affected in that way still seem to do well for me, so I'm not certain whether this spells doom for your rose. However, it might be a good idea to keep it isolated from other roses so that this process doesn't spread further. I'm sure others here will be able to advise you more precisely.

Maybe, downy mildew? Peranospora sparsa.

Yeah, I see the discolorations turn purple. If it is, they will eventually turn necrotic -- silvery, dead tissue.

If it is, here's information -- you should be able to find a lot more.

http://universityofillinoisplantclinic.blogspot.com/2012/05/downy-mildew-of-roses-peronospora.html

It is a disease that shows up after wet winters .... and significantly, after wet winters where the roses are commercially grown (like SoCal's south central valley.

We had NO good luck with fungicide for this fungal disease, but instead got better results with FRESH horse manure, spread inches from the base of the plan, out to the drip-line. But I would not be comfortable doing that with a newly-potted rose.

Personally, I believe I would return it to where you bought it.

Mind -- This is not a certain diagnosis. Best I can do, with photos.

Mind, my husband says he doesn't think so.

Thank you. It was one of several roses I bought and I didn't pay close attention to each in the store because the owner selected the pots and had a worker load them into my car. All other roses look fine except for this one. I wasn't sure if these were diseased canes or had some winter damage.

I don't know if they have any left to replace it... if it's not mildew but perhaps rose canker or something else, can it be saved?

Looks like transport damage (at least one cane looks like the thorns were rubbed off, like it was rubbing against something in transport) or sun damage to me. If so, then all those buds growing out will quickly outgrow the damaged areas, then you can just prune off the canes if they die back. IMHO, give it some time and you will see.

If it were mine, I would put it somewhere not too close to other roses (make sure it has good sun and water), and WAIT to see what it does. Looks more like damage than disease to me too. If the buds grow out to healthy looking canes, then you can cut off the parts which may die back.

In the meantime, I might spray it with a product made specifically for downy mildew called AGRI-FOS, just in case. Be sure to follow the directions. I have had downy mildew on roses before, and it can kill them. I have had good results with AGRI-FOS - practically the only time I ever spray anything on my roses is if I suspect downy mildew. (I am sure Jeri's suggestion of fresh horse manure works too, but I agree with her that that is not a good idea for a baby rose.

Jackie

I think it looks like downy mildew. I get this in my rose garden when it it gets warm but the nights are cool. You will need to take action of some kind or will go through your garden, and destroy other bushes. For the last couple of years I have been using Superthrive to try and keep it out of the garden. This year, I had only one bush that seemed to get it.... however, I first misdignosed it because with the Superthrive, I was only getting spotty leaves, not the whole canes turning colors..... I managed to get some fresh horse manure on jerijen's advice (and the fact the mounted police came through the neighborhood). The plant is looking better. If you have a local rose society close you can ask a rosarian to come out and verify in person.... Good luck

I want to thank you all for your kind advice. In the end, I spoke to the nursery and I was delighted with their response. They weren't sure what was wrong with this rose but said that it definitely didn't look well and apologized for it. They right away offered a replacement or refund. Of course, I went ahead with a replacement. Your responses were very educational nonetheless and many thanks again for it.

Glad you got a replacement! Just wanted to say many of my canes look like that after winter & into spring. I always just called it "canker" and pruned them back to a healthy spot as best as I can. I assumed it was freeze/thaw damage. Just wanted to add in my experience because I'm in a similar climate as you. I would not purchase a rose with canes like this though. If I buy in the spring I want them to look greenhouse perfect, because it will be the only time that they will look that great!