A good question. I guess it will take a fair bit to feed a family of 12. But root vegetables like potatoes and carrots is a good safe bet I guess for basic agricultural crops. If possible some wheat for grains but not sure how much space that would take. Supplementing that with fish and other game, and top that of with some hens to lay eggs and a few sheep for meat (and make your own yarn) and a cow for milk and I think you should be fairly set.