A million calories per acre

VermontCathy Posts: 1,980 ✭✭✭✭✭
edited December 2021 in Garden Design

The Permies forum is discussing a "Million Calorie Challenge". It would require that a mix of different crops be grown, not just a high-calorie crop like potatoes. What is necessary to produce a million calories of vegetable food on an acre?

An acre is about 43,560 square feet, or 4,047 square meters. That works out to 23 calories per square foot, or 247 calories per square meter.

Most vegetables and fruits have little fat (unlike nuts and animal products). Both protein and carbohydrates have 4 calories per gram, so that converts to 5.75 grams per square foot, or 1 oz of food per 5 square feet. (Or in metric, 43 grams per square meter.)

Those are really low numbers, suggesting that it's actually quite easy to produce the equivalent of a million calories per acre.

Does your garden produce at least 1 oz of food in every 5 square feet? If not, what would it take to lift it to that point? Could you do it with no outside inputs?

It's an interesting goal, and should be doable for most gardeners.


  • marjstratton
    marjstratton Posts: 1,132 ✭✭✭✭

    Would be interesting to try. I certainly do not have a whole acre under cultivation.

  • Michelle D
    Michelle D Posts: 1,465 ✭✭✭✭✭

    I saw that discussion yesterday also. It is a really interesting idea. Living within city limits, I don't have anywhere near an acre, but the idea got me thinking. How much could I realistically grow here if it were my only option for feeding my family. After looking up some numbers from the Bio-Intensive gardening method it is pretty encouraging. My problem is making sure not to start too much new stuff all at once. I do that way too often and it gets overwhelming. I let my excitement get the best of me. 😕