P.S. I forgot to mention - after it is in a pot outside which drains well, water it, but do not feed it anything until it recovers. Then, only when it is putting out new growth, it is OK to feed it with any sort of rose food (again, food only - not multiple products).

Jackie

I have the same black stuff going on on my Dark Desire rose that is planted outside in the ground... It doesn't go worse as time passes... but rose itself is just sitting and doing nothing... Don't know if there is a connection or just coincidence.... I decided to let it do its thing until it cools down a little bit to act...

My best guess is sooty mold. https://www.rhs.org.uk/advice/profile?PID=770 and http://ipm.ucanr.edu/PMG/PESTNOTES/pn74108.html 

It has been outside, I just pulled it inside to take a picture in better lighting since it was night when I got home. I didn't realize the pot was too small though! It was a bit larger than the one at the nursery so I assumed it was enough. But I will repot it in something much larger abs with better drainage. Thank you!

There isn't any mold on the leaves. The dark spots are in the leaves themselves, not something that can be washed away.

Thanks for the better picture. Does look like some sort of fungus - after it settles down in its new much larger well draining pot (no saucer, nothing under it except something to hold it above the ground a bit), I would wait at least 2-3 weeks, and then take off the damaged leaves, and spray with Bayer Advance Disease Control. As I said, when it starts to put out new growth, you can feed it.

Just so you know, the reason I suggested cutting off all of the blooms and buds right now is that if you don't, the plant will spend energy making hips and blooms when what it should be doing is growing more roots. You can let it bloom when it is well.

Please post pics of it on here when it has recovered!

Jackie