If all you want to plant are vegetables, there is no zone (two lower) requirement. Basically, the veg. die when it is below zero, most of the time. Some stay alive even at -9C. If you cover them with transparent plastic to block the wind and trap the heat, they will even last longer. At night, if it is below zero, you can always bring them into the house. I installed light fixtures next to the window so that I can grow them all year round. I just started to do that and see big difference in their growth compared to no light before. Also, watering them with fish emulsion and seaweed concentrates makes a big difference in growth too.
If your season is long enough, growing peppers and tomatoes are possible. If the pots are dark, it will attract heat to the roots.

If it faces the East only, then there may not be six hours of sunlight. Therefore, it may be better to set up a florescent light fixture to grow your cherry (for pots only), flowers, lettuce and spices in the house all year round.