Yes, plenty of perennials such as sedum \'Autumn Joy\', Euphorbia, heuchera, rudbeckias, and phlox will survive cold winters but the trick is the type of pot, the size of the pot, and how protected the container is from the elements. Clay and ceramic pots may crack but synthetic containers offer some insulation but need good drainage. Wet winters may rot roots so placing pots under house eaves can save them from drowning. Larger pots much better at overwintering plants than small ones. Think half whiskey barrel in size or at least 2 feet deep and 2 feet wide. You may also want to contact or attend a meeting of the Spokane Garden club or visit the Master Gardeners in your area. They know all the tricks at getting perennials in pots to overwinter in your climate. Keep growing, Marianne Binetti