IrishCrow
Mame
Well the past few years it's been mild but pa has a real good potential to get brutal. I'm in the mountains so if it's a bad winter the air can get below 0 often. Again same thing with the snow. We get slammed with blizzards too but last couple winters we didn't get squat. I have a red maple, a couple small white pines, a azelea, and a couple junipers.Curious....what's "a bit cold" in northeast Pennsylvania? Below zero for extended days? Extreme wind chills? Lots of snow accumulation...that stays and stays....or do you get quick melt-downs with temperatures up-and-down a lot?
And.....just wondering.....what kind of trees are you storing?
I think the tricky thing with a greenhouse of any size, and even a cold box, is keeping it consistently cold during the winter until the real spring arrives.