Most soils are made up of a mixture of sand,silt and clay with varying amounts of humus.
A sandy soil has very little humus. Since the particles in a sandy soil are large, it has a coarse texture with plenty of space between the particles. Hence , it is well aerated but water drains through it quickly leaving it dry. It is not a good soil for crop cultivation.
A clayey soil is made up of very fine particles with very little space in between them. As a result, it becomes easily water logged during the wet season and is poorly aerated. During the dry season, it hardens and cracks. It is also not a good soil for crop cultivation.
Loamy soil contains a mixture of sand and clay particles with plenty of humus. It has a good crumb structure which allows water to drain through it, while holding back just enough for plant growth. It is well aerated and rich in plant nutrients. This is the best type of soil for crop cultivation.
Sandy and clayey soils can be improved by farming techniques and used for crop cultivation.
