Farmers plant clover into the wheat crop to help build the soil and put a lot of nitrogen into the soil, as well as feeding various other soil building organisms like earthworms.
It was crop rotation so the soil can replenish the nitrogen.
Peas and beans belong to a very special group of plants known as legumes. Legumes are plants which have a bacteria living symbiotically in their roots which "fix" nitrogen for use by the plants themselves and thos that eat the plants. By planting legumes every 3 years, the farmers were using a natural form of nitrogen fertilizer!
about 11 years.
Over 200 medieval and Renaissance fairs are held every year, and includes the Alabama Renaissance Faire.
A method in which farmers move every one to three years to find better soil.
Yeomen were small, independent farmers, who were required to serve as archers, as required. To be a yeoman, one had to be of age, which might have meant 18 or 21 years old. There was no specific age of retirement.
Mostly on farmland because of chemical fertilizers, which over several years will tend to acidify the soil somewhat. That is why farmers "lime" their fields every few years.
Crop Rotation
About a thousand years
the One hundred years war
medieval maps were made out of parchment before the Chinese invented paper a few years later
5 years