I have been to Alaska numerous times, always in the summer months though, and I have seen some of the most gorgeous flowers, similar to what is seen in France and Belgium in the summertime. I think the looooooooooog days more than make up for the shorter growing period. At least that's my theory.
March, here in NE Mississippi can be wonderfully warm and sort of dry (with all our humidity, we are hardly dry!) one day/week and can be freezing/rainy the next. The winters of 2010 and 2011 were very mild and we had an early spring, and I was able to put my dormant plumeria in pots and outside the last week/first week of February/March. Last winter was sort of mild, but we had a cold/wet March and my plumeria did not go out until the first of April. This winter, well you know. I have no clue whether we will have an early spring (doubt it), a normal spring, or a late spring. Just when we start to have more typical winter weather here, the National Weather Bureau has issued a winter warning for Monday night and all day/night Tuesday, with lows in the 20's, high in the mid to lower 30's, wind from the north and snow, sleet, and icing.