Depends what variety of rose they are - if they're climbers or bushes, now is the time to prune, though as they're young, that may not be necessary this year. If they're ramblers, September is when you prune those, but its hard to be definite - the vast majority of roses are grafted onto a different rootstock to supply vigour to the variety grafted on top - you have presumably collected seeds from the variety on top, and now they're growing on their own roots, so how well or fast they'll grow is hard to predict, as is the pruning requirement.