Are we cool enough yet, or should I wait a little longer? I want to try it out this year. I only have a 50% success with my other cuttings method.
In my experience and in my climate and conditions, no, it is not time to wrap cuttings. My success here comes from using material which is not actively pushing new foliage, canes nor flowers and which have not pushed any new growth for many weeks. Here, as long as the weather actually turns 'winter', instead of remaining warm enough to encourage continued flowering, that is most often late December through mid April. That varies greatly year to year depending upon whether 'winter' actually occurs or not.
My impression is, wrapping cuttings which have not become as dormant as possible fails because they contain insufficient stored resources to permit them to callus and support themselves until they root.
There are many variables which can greatly influence results and these will vary greatly from climate to climate as well as one rose type to the next. So, your mileage is going to vary depending upon where you are and what roses you are attempting to wrap. If your conditions are generally like Southern California, Zone 10, arid, hot, "savannah" type, now is probably not the most appropriate time because the condition of the cutting material is likely not appropriate to permit it to succeed using this method. But, try it. Perhaps you might find it can work for you in your conditions now. It hasn't in mine until roughly the time period I stated above. Good luck! Kim