Depends on a lot! My reds are fast growers but I planted some fingerlings and they took two months. It also depends on how much soil you put on top. I only add about three inches and then mound around them as they get taller. If your spring has been really wet they could have rotted in the ground. It happened to me last spring. Lost two fifty foot rows of reds :( I'd dig one up if I were you and see. You can always put it back.

Established, in the ground roses, can handle fairly cold temperatures. Exactly how cold, I honestly don't know because I've never had spring damage on anything that remotely belongs here. The year we had a night of 18°F in May, and the apple crop was totally wiped out, the HTs were damaged, and the neighbor's Japanese maple, but that was really it. The other 130 roses and all the perennials didn't even seem to notice anything abnormal had happened. Potted roses start growing early, so they are out of sync with the weather. Those should come in when the temperature is going to be below about 25°F. We have a forecast low of 30°F tonight, but it's cloudy and wet, so we are unlikely to get much below that. Everybody stays out tonight. We are warm blooded animals. Roses aren't. Roses are hardy plants (or at least they should be) and their version of nice, comfortable weather isn't remotely the same as ours. I think it's pretty miserable out, and have a fire going in the fireplace. The plants outside are probably doing a happy dance, because it's good spring weather for them.

You are in zone 4? As I remember you had some pretty cool weather until recently. I wouldn't get out the shovel yet! I dug up two roses yesterday, and found that while they had no signs of life above ground, they did have live root growth and some swelling leaf buds below ground. I potted them up to give them a little babying. Your area is still warming up, so you may see some growth. It was a hard winter for our area too, but with all the grafts buried, all the HT's came through, most killed to the ground. One just broke dormancy last week. Usually, I give up on them if they show no signs of life by June 1st, but this year is a bit different. Please forgive any spelling errors - I'm typing without my glasses this morning!

what does it matter... there isnt anything you can do about it ... in spring.. any improperly hardened off parts.. will have blackened... and you can prune it out ... this is one reason i NEVER fert trees.. shrubs.. and conifers ... they are not children.. they dont need to be fed ... ever .. IMHO ... if something is lacking in the soil.. based on a high level soil test.. that has nothing to do with 'feeding babies' ... was yours a recent transplant.. if so.. and you didnt bare root the plant.. you also have incorporated fert .. so you may have doubled up on such.. by adding more .... ken ps: i am going to bet.. its not going to be a huge problem in your zone ... compared to froze solid MI in winter ...