I have two "Endless Summer" Hydrangeas planted in the front of my house near the street (basically a wind tunnel). I know the temps are supposed to go below freezing tonight and was wondering if there is anything I need to do to my hydrangeas to prepare them for winter. They did bloom all summer, not even close. I have heard that I am supposed to cut them back before winter. Any truth to this? Any help would be appreciated ASAP as it's getting mighty cold outside. THANKS!