How do i grow sweet potatoes? I know its probably too cold in the uk, but do...

I know its probably too cold in the uk, but do you freshly plant a seweet potato in the ground?
What is the process of growing a plant...
Answers:    This have a lot of info for growing them contained by the UK:
http://www.rhs.org.uk/advice/profiles050...
You can buy the plants locally or online, they ship well.
Plant expert needed!?
I tried growing them here within Minnesota,USA a number or years ago, and they did not do very very well, I just get tiny little things that weren't worth eating...I consider the season is too short and the temps too cold for them to really do well. I ordered from a catalog and get little plants, but I would guess you could also grow them like potatoes from a piece of tuber.
I want to grow rattan from my neighbors...