Here, the common practise is to spray almost everything with copper sulphate / bordeaux mixture as a preventitive measure in the winter months. I guess it also prevents early awakening of the tree if the weather goes hot (correct me if I am wrong please). Last winter, my gardener sprayed everything with bordeaux mixture, including the japanese maples twice with one month interval. This year, before letting him do it, I would like to know first whether this is a correct thing to do and whether it can be harmful in anyway for my trees, especially the japanese maples. What do you think about this? Should I go ahead and spray them? If so, when and how many times? Do you advise anything else instead of bordeaux mixture / copper sulphate to use in winter as a preventitive measure, or anything to be used in addition to it? Since my climate is at the edge for japanese maples, I would like to make sure I do everything correctly. (I am in Izmir Turkey, next to the mediterranean sea. USDA zone 9b) Thanks in advance.