The easiest way to address soil acidity is to purchase roses grafted on multiflora rootstock--they will grow better than roses grafted on Dr. Huey--even if you just stick them in the ground without amending the soil first. I just got a bunch of nice roses from Palatine on multiflora rootstock. And, unlike Dr. Huey, I don't get new roses from fragments of root left in the ground. Bone meal is an organic source of both phosphorous and calcium, but I don't like to use it because animals will dig it up. Adding some lime will help with both acidity and calcium. Bloom booster fertilizers are high in phosphorous.

Yes, just buy roses from Palatine, and that will solve the problem. It is something to keep in mind if you also grow vegetables or lawn, though. Very standard east coast results.

I have a sandy soil with a pH of 5.5 & my own root & multiflora grafted roses are doing just fine. Since your soil test says you need some Ca, adding lime will raise the pH & add Ca at the same time. Lime is inexpensive, safe to use, can be added any time of the year & slow acting so I would lime the the entire bed....hopefully your soil test gave you some suggested amounts to add. As for the P, adding some compost & a layer of organic mulch, that will break down over time, will add some P in the long run, And if you still think some more is needed, use Zack's bloom booster suggestion.

I agree with Lime(calcium carbonate).

We here in the southwest have the opposite problem: our soil is high in calcium and P and our pH is high.