> It takes 5+ acres in a decently arable region with fertilizer to feed one person. By the time you're providing for a significant fraction of your caloric intake, it ceases to be a "garden".

I'm sorry, but I just can't believe that. Is that fudged to account for livestock or waste or something? A single acre is what, 40*100m? That's huge, you could feed a whole family all year on potatoes, peanuts, greens, squash etc