Yes, i personally would. Also, keep the plants as cool as possible and keep them on the dry side to slow down growth.

Thank you very much, Badfish. I'll leave the door of the (unheated) greenhouse open from now on, as it might be a bit TOO cool to put them out in the cold frame??

Good frost here this morning, I guess you could move to cold frame and cover at night, its always a difficult time isn't it, they go leggy so quickly

Thanks Pam. Yes, it's a bit tricky, but these plants are so well established now, that I think they'll cope with a little extra fresh air :)