Cold Hardy Hibiscus
We ordered some cold hardy hibiscus, the Rose of Sharon type, from a catalog. This was last year ad they came as small plants. The dogs dug up 5 of the 6. We're not sure exactly which one survived but point is, it went through the winter, complete with snow, ice and several days in a row below freezing, and it's coming back! Little green buds on it now. And the stem stayed flexible and "alive feeling" all winter.
We also have a Red Luna that rises from the dead like science fiction. It dies back completely each winter, has been tilled over and moved, it still lives. Hasn't started coming back this year but I bet it will. Still early.