Wheat is the single biggest food crop in the world today, and it was also the basis for the heart of the medieval diet, bread. Planting wheat around the world requires clearing off other plants and trees, to be replaced by fields of food. Now in 2022, the war in Ukraine is disrupting wheat growing, a real problem because Ukraine has been a major provider of wheat to third-world countries. Wheat production has really expanded world-wide in the last two or three generations, due to modern fertilizers and improved hybrids and farming methods, but the danger of relying too much on one ubiquitous crop is dealing with its absence.
Wheat has been cultivated for close to 12,000 years, starting in the Middle East. Without agriculture, you really cannot have cities (or civilization), because you need a reliable crop that will feed a lot of people without everyone having to go out and hunt and gather every couple of days, said hunting and gathering requiring that people be fairly widely spread out, so they don't exhaust local resources.
Medieval wheat was primarily winter wheat, planted in the fall, sprouting but then lying dormant through the winter, ready to start growing for real as soon as it warms up in the spring. It would be harvested around July. One can also plant wheat in the spring, but the most common spring-planted grains were oats, rye, and barley, barley primarily around the Mediterranean, rye and oats in more northerly climates. You can make bread out of any of these, but it was uniformly agreed that it was inferior to wheat bread. For one thing, those grains don't have as much gluten, meaning bread wouldn't rise nearly as well.
Farm work was thus spread out, some grain planted in the spring, wheat harvested in the summer, non-wheat grains harvested in early fall, wheat planted in late fall. The three-field system of crop rotation, where one of the three fields lies fallow every year to theoretically regenerate itself, thus provided work spread over the months and a fall-back if there was a disastrous wheat harvest.
(People with ceoliac disease, intolerance to gluten, would have been in serious trouble in the Middle Ages. There was no "gluten-free" aisle at the grocery store, and for that matter no grocery store.)
Wheat is derived from wild grasses, bred over the millennia to have more seed heads (which is why modern wheat needs a lot of fertilizer) and to have the seed heads not easily break away from the stem. This makes it easier to harvest, whereas wild grasses have the seed heads break loose and disperse if the stalk is disturbed. This is fine for wild grasses spreading themselves, but it makes for a difficult harvest.
Wheat thus had to be threshed and winnowed to get the seeds free of the stalks and hulls. Threshing required beating it once in a barn, to break the seeds free, and winnowing, that is separating seeds from hulls. On a windy day winnowing could be achieved by tossing the wheat and hulls in the air so the lighter chaff would blow away.
Because it needs no refrigeration, wheat could be easily stored. The problem was keeping out mice and rats. Medieval cities tried to stockpile grain against bad harvests. With wheat, the grain, the food, is also the seed for next year's planting, so if there was a bad harvest there was always the unenviable choice of eating the grain now, to keep from starving, and then having little to plant, meaning starving next year.
Wheat stalks were valuable in the Middle Ages, because they were an excellent source of thatch for thatched roofs. Modern wheat no longer has the very tall stalks it did then, because it has been deliberately bred for shorter stalks (to put more energy into the seeds instead of the stalk).
© C. Dale Brittain 2022
For more on medieval food and farming, see my new ebook, Positively Medieval: Life and Society in the Middle Ages. Also available in paperback.