There definitely seems to be a difference in varieties -- I had the Butterballs and Red Gold potatoes growing side by side, and the Red Gold plants were dwarfed by the Butterballs. Same for flowering -- I've had some types that never flowered at all, others that flowered profusely.
They do grow well up here, though -- and are grown commercially, which usually means that potatoes are pretty cheap in our stores; leading me to wonder if it's actually worth it for me to grow them... Like tomatoes, though, there are SO many varieties to be tried!
