If the writing has disappeared it is possible that the feed is so old it will have lost at least some of its nutriments.

Thanks Moongrower will blood fish bone be ok for the roses?

If the feed is granular, a handful distributed round the base of the rose and turned into the soil now, and again in six weeks - but not later than mid June.
Fish blood and bone will be okay - but it doesn't have the trace elements contained in specific rose food.