I received 2 MINI roses in pots. This spring I planted them in my "garden" which has dirt 2 feet deep. It is almost like a giant pot. They aren't in the ground. The roses thrived and bloomed twice this year. Now -- winter is almost upon us. Without digging them up, can I cover them with a tarp to protect them? I can't very conveniently bring them in (the container & dirt weighs a lot). I live in Ogden, Utah and the REGULAR roses are obviously not dug up and bloom every year - beautiful.