have a client with those climbing/running roses. they have gotten out of control and need pruning. located in mostly sun with late afternoon/evening shade. will using the hedge trimmer be okay? time of year? i am hesitate to trim now as we are in mid-90's w/index in low-mid 100's. I should also mention that portions of them are also invested with some sort of running vine, very fine and easy to pull or rake off roses. advice??