Trimming bushes

I have a query about making my roses bushes more bushy. Say one has several canes growing straight up with roses on top. Would it cause any problems if I cut the canes in half to make it grow thicker or should I stick to minor trimming while it's summer? Thanks

I would restrict any prunning at this time of year to a Summer prune (a heavy trim) to have the best possible flowers in th Autumn. When pruning radically in the Summer you run the risk of exposing your roses to sunburn which can be devastating. Some years back I pruned a stand of five Joyfulness mid Summer as an experiment and it took them three years to come back to normal.

Thanks Ausrose, I shall restrain myself and leave them alone..