Dark-colored soils: Dark-colored soils, such as black or dark brown, usually indicate high organic matter content. Organic matter is rich in essential plant nutrients, such as nitrogen, phosphorus, and potassium. These soils are often fertile and can support vigorous plant growth.

Light-colored soils: Light-colored soils, such as white, gray, or pale yellow, usually indicate low organic matter content. These soils are often less fertile and may require additional nutrients to support healthy plant growth.

However, soil color alone does not determine fertility. Other factors such as soil texture, pH, drainage, and nutrient composition also play crucial roles in determining soil fertility. A soil analysis is recommended to accurately assess soil fertility and determine specific nutrient requirements.