Home suburban gardening is quite different from providing ~2000 calories per person per day for a family. Depending on the source, I found a figure of 5-10 acre

Home suburban gardening is quite different from providing ~2000 calories per person per day for a family. Depending on the source, I found a figure of 5-10 acres per person needed for a year's food (for a 100% vegetarian diet, no livestock). So for a family of 4, you'd be looking at 20 acres or so, minimum, which is approximately 1000x1000 feet.