Q.How long do I need to protect rose cuttings from freezing
I have 40 rose cuttings doing very well. I live in northern California. I’ve used a cold frame to keep them from freezing, but they are doing well – some have a couple of inches of growth. I’d like to re-pot, but they won’t fit in the cold frame any more. Do I need to keep them from freezing once leaves have opened up?
I see you have been waiting a while for an answer. I take that to mean no-one is quite sure what to tell you. Preparing for winter temps takes several weeks in the fall. I don't think you can engineer or replicate that process now. Because of all the effort you've put in so far, I would continue to protect the cuttings until after danger of a freeze is past, temp 25 F. or colder. f you put them out soon, you could use a row cover and hoops to cover them when frost is expected. It would be a shame to lose them!