Clay soil is a very fine natural type of soil containing clay minerals. Clay soil develops plasticity when wet but becomes hard upon drying. This type of soil is suitable for growing crops because it is good at retaining water and is rich in humus and very fertile in nature. The crops that can be cultivated in clay soil are buckwheat, clover, winter wheat, and vegetables such as broccoli, Brussel sprouts, cabbage, and kale.