What was rotation in the Middle Ages?

Answer 1

A field rotation system was a schedule for planting different crops so the same crop would not grow in the same field year after year. The early system used in the Middle Ages was the two field system, in which the field was tilled for a crop one year and allowed to recover the next. Later, the three field system was used, in which a field was tilled for one crop one year, tilled for a different crop the next year, and allowed to lie fallow to recover in the third. Fallow fields were used for grazing.

Answer 2

I think you are probably referring to crop rotation.

During the time of the Roman Empire, farmers used what was called the two-field system. A field was plowed and planted, the crop was harvested, and then the field was allowed to lie fallow for a year, with animals grazing on it.

In the Middle Ages, the three-field system was introduced, in which a field was planted with one crop on one year, and then with a second, different crop the next, with a fallow time on the third. This increased the amount of land being tilled by a third, without changing the amount of land being farmed at all. It also produced healthier crops.