To maintain the fertility of the soil following natural methods are used:
(a) Field fallow: The land is left free or fallow for one or more seasons to naturally regain the nutrients.
(b) Mixed cropping: It is the practice of growing two or more crops simultaneously on the same piece of field. For example, if a cereal crop such as wheat is grown along with a leguminous crop such as pulse (e.g., gram).
(c) Crop rotation: It is the process of growing a crop in between two similar crops. For example, wheat crop is planted during the month of November and harvested in March and April. Rice crop is planted in June–July and harvested in October November. Now in between these two seasons, the land lies empty. Instead of leaving it as it is, the farmers plant a pulse crop in this time.