Good afternoon Isabelle,
I live just South of you in New England and I have a North facing, 10 acre homestead. Plant choice is key as we both experience difficult Winters. As you already know, the snow won't disappear until May on a North-facing slope and some plants won't do well. Match your plantings to your region. The entire Maple family grows well in Quebec. There are hardy versions of apple root-stock that weather Winter very well; however apple blooms can suffer with an early frost. Some veggies love that North-facing slope (Swiss Chard, broccoli, etc). And there are some chickens that have specifically been bred to survive the cold as well (I have a small flock of Barred Reds). You should have plenty of Red Raspberry, Black Berry, Choke Berry, Blue Berry, and Cranberry in your area. They grow much like weeds in some environments.
Of course some plants don't do well in such a slope (tomatoes and peppers come immediately to mind). For those plants I STRONGLY recommend building a green house so that your tomatoes turn red and the peppers actually produce fruit. Our green house is a god send year round. You can even plant arugula and Swiss Chard in there for Fall and harvest those greens into early Winter.
I do recommend that you ask around for a 'farm goddess' to help with identifying varieties that grow well in your area and where to buy the proper seeds locally. Down here I stick my head in at Agway, which is local. There are a couple of seed houses located in Maine (
http://www.johnnyseeds.com) and Connecticut (
http://www.rareseeds.com) that the wife uses regularly.
Does this help??
Rgds