Pretty close to zero. BUT ...
You might see what happens if you refrigerate them over the winter, like stratifying seeds. You might sear the ends of some with a torch as this may help (i.e., find out). Then, next spring cut back the ends, dust with rooting hormone and strike them. Every piece must have a node (a pair of buds) and not much will happen until the leaves are expressed, then it is a race against desiccation, so you will need to affect some kind of terrarium and keep them in shade.