Posted: 09/08/2013 at 21:14
Keeping the worst of the rain off of them is the main thing rather than protecting them from the cold. However, if they germinate before the winter, things get tricky and they would need something like your plastic greenhouse, Red Dahlia.
Gill, you water once when sowing them and only need to keep the compost slightly damp after that.
Have a read about cold stratification here: