Preparation of soil : Preparation of the soil is the first step in growing a crop. It involves tilling and loosening the soil. This allows the roots to penetrate deep into the soil and to breathe easily even at greater depth. Loosening of the soil helps in the growth of several microorganisms, earthworms, and more that enrich the soil with humus and other essential nutrients. The process of loosening and turning the soil is known as tilling or ploughing. This is done by using a plough or cultivators.