Wow, Pitangadiego mentions Dwarf Orinoco! Quite contradictory information! I allways thought that would be one of the hardiest ones.
I second Bigdogs observation about the cavendish-types. I have seen what a week of 40s-50s weather in Trondheim can do to a cavendish planted in ground. Turned to mush. The sikkimensis next to it still grew.
Erlend