On average, the yield of fresh mint at the mint harvest is 15-20 tons per hectare. On average, the peppermint oil yield is 58-68 kg per hectare. On average, the yield of dried mint is 3 tons per hectare. Note that 1 ton = 1000 kg and 1 hectare = 10,000 square meters.
The figures above represent the average annual yield and are obtained when harvesting healthy and mature (over 1-year-old) plants grown by professional breeders. Remember that yield is highly dependent on many parameters (variety, climate, soil, fertilization, irrigation, weed control, harvesting, distillation methods, etc.), so these figures vary from grower to grower. The possibility of rain or other stressing parameters can cause a drastic reduction in all of the above yields.
For obtaining mint essential oil you can choose one of these extraction or distillation methods. One of the best-known and widely used is the distillation method.