Conservatively each person needs 1500 calories per day and that's cutting it close. That's about 2 million calories per year for 4 people. Potatoes are one of

Conservatively each person needs 1500 calories per day and that's cutting it close. That's about 2 million calories per year for 4 people. Potatoes are one of the most calorie-dense vegetables by weight and by growing space. They have 350 calories per pound, so you need 5700 pounds of potatoes to feed a family of four. A good potato yield is about 25,000 pounds per acre, so you need nearly a quarter acre of potatoes (1000 square metres) to feed your family for a year.