Im in the UK in Yorkshire - just thought Id mention that I successfuly grew Ginger in a pot in my greenhouse. Its not a heated greenhouse but the plant grew pretty tall - about 24" tall with about 20 odd leaves/growing spikes. Now that were in winter it is slowly dying off but from what Ive read that is expected and fine.  Im going to empty the pot as soon as its died back and see what I can save for next year or if theres enough to harvest.

One thing though - usual shop-bought ginger root from the supermarkets (at least in the UK) are treated to stop them sprouting so its best to get roots from a garden supplier. Bizarrely mine came from Homebase as an impulse buy in Feb!