If you're hungry, you plant dense staple crops - an acre can yield something like 10 tons of potatoes (or carrots or pumpkins) - if you're not selling produce,

If you're hungry, you plant dense staple crops - an acre can yield something like 10 tons of potatoes (or carrots or pumpkins) - if you're not selling produce, then even planting 0.1-0.2 acres of potatoes means you'd have more potatoes than your family needs (because you eat lots of other things). It also takes a lot of labor if you don't have specialized machinery and will take a lot of space in the basement, but it will keep you from starving even from quite small plots of land. A fruit tree is great, but the proper time to plant one is ten years ago.