Ginger, it's the best suggestion I ever got (asked it also on a Belgium and Dutch garden forum).
It should not be hardy in my zone 6 , but some pictures show how weird the stems grow for a Lupine, like they did here. And maybe the first winter was not that cold (I can't remember). Although: I winter sowed the 2011 seeds this year and very surprising they already sprouted. It's still freezing here, but the sun warms up the containers so now and than. Hope they survive, because temps are going down 14°F during the night.