Hi all, I've moved from Fraser Valley to West of Williams Lk. a zone 3a. I dug up my phlox last fall and put into 4" pots for the move. I never got them into the ground this spring, was unsure where to plant them. They summered and flowered nice. However, winter is coming now, and they are still in pots. How should I winter them? We've built a wood frame greenhouse w/ plastic and big glass windows facing south. Do I keep in pots or store as root stock? Thoughts and comments please. Thank you. Oh ya, it got to -35 C with 3 ft of snow.