Calculations on wheat production

lathechuck's picture

Somewhere, I once read that wheat is such an important crop in the world because it is the most productive capture of solar energy into food calories. (This claim must be understood in a particular context of wheat-compatible conditions of climate and so on, of course.) So, I have wondered: how much wheat could I produce in my suburban garden?

The 2020 world record for wheat productivity, says the Internet, is a farmer in New Zealand who harvested 207 Bushels/acre. The typical productivity in the US is now 40-48 B/ac, with 29-119 being the range. (I guess, if you can't get 29 B/ac, you don't bother planting.) To get 207 B (at 60 lbs./B, 12,420 lbs.), the farmer applies 267 lbs. of N, 40 lbs. P, 89 lbs. K, 78 lbs. S, and 62 lbs. of seed. Irrigation wasn't mentioned in the article, but was probably used. It also wasn't clear whether this yield was one harvest, or the sum of two or more harvests within a single year.

In my garden, I could imagine dedicating one 4x12 plot to wheat. Scaling the record-setting productivity down to my scale, I end up with about 0.28 lbs/square foot, or 14 lbs. for the plot. Last week, I brought in 30 lbs. of butternut squash from that plot, and there's probably at least another 10 lb. on the vine. But the water content of winter squash is 81% (summer squash being 98%!), so let's say 50 lbs. of fresh squash equates to 10 lbs. of dry (10-12% moisture) wheat.

If I could grow wheat at the typical range of productivity, rather than the NZ record, it looks like the two crops would be competitive, on a dry weight basis.

lathechuck's picture

I don't know what the record is, but a typical harvest of dry beans (white, soy, etc.) is 1500-1800 lbs./ac. (20-30 B/ac). However, a trial in Michigan produced 4849 lbs/ac. of black beans (which are reported to be more productive under organic growing conditions than white navy beans (https://reeis.usda.gov/web/crisprojectpages/0222485-organic-dry-bean-pro...).

If I can figure out how to keep the rabbits and deer away, I'll probably start growing beans again.

Which is the crop with the most calories per acre?

Sifting through the available data, it looks as if field (dent) corn is the winner. The most reliable data show potatoes over sweet potatoes, and field corn over potatoes. The record (reliable) yield for any crop is over forty-four million calories per acre: field corn. For protein, it’s soybeans.
https://short-facts.com/what-agricultural-crop-produces-the-highest-numb...

There seems to be a fair bit of variation in which crops produce most depending on how you're measuring, but wheat isn't typically in the top two.

mountainmoma's picture

Calories are the most important first thing, but then you also have to balance nutrients, like protein or vitamins. Then there is also the measurement of time, so haw much calories and nutrients from a field. Some crops are short, and then you have succesion.
SO, not just one crop. Growing in small areas vs a large mechanized farm you go heavy on succesion. If you have short season dry corn and short season potatoes out here you can have a crop of each from the same ground. If you can overwinter winter wheat, once it is harvested, you will plant something else. Maybe beans, maybe turnips, etc....

Other considerations have to do with water and seasons/weather wildlife at your location. Some areas are great for growing wheat with no irrigation. Wheat is higher protein than dry corn ( dent is not the only dry corn, I prefer to grow flour corn) The crows here dig up the corn seed and leave wheat seed alone. Corn seed is easier to plant by hand as less seeds are planted, etc....

Anyway, potatoes have vitamin C as well as calories. Grains are great, like wheat or flour corn to make breads with. Turnips or rutagegas have 2 edible crops, the high calorie root and the greens. The greens give vitamin A, calcium and other nutrients that you do not get with potatoes or grain. They are brasica, cruciforous, family so greens have that vitamin range like kale or brocolli.

While beans may make a good compliment, if you have forage, goat milk products are way easier than growing beans as far as human labor hours go ! That is why there have been so many historical human organizations based on sheperding. That gives a lot of calories and nurtrients for the amount of human labor. It is easier to feed a couple milk goats than chickens to get eggs actually. In my location ! But, that does vary by location.