Regur soil, also known as black cotton soil, is a type of soil primarily found in the Deccan Plateau region of India. It is rich in clay and has a high moisture retention capacity, making it suitable for growing cotton and other crops. The soil is formed from volcanic rock weathering and is known for its dark color, which is due to the presence of iron and magnesium. This soil type is characterized by its ability to expand when wet and shrink when dry, which can lead to cracks. Regur soil is also rich in nutrients, particularly lime, calcium, and potassium, making it fertile for agriculture. Its unique properties support the cultivation of various crops, including sorghum, millet, and soybean.