Red clay derives its color from iron oxide, and is usually created through the breakdown of rocks in lower substrates. Red clay is technically a subsoil, and it is usually found only where true topsoil has eroded. Poor agricultural practices and soil-stripping development of rural areas have contributed to its prevalence in many areas.
Because of the clay’s unique composition, red clay soils are often rich in minerals. Calcium, potassium and magnesium are all loaded into red clay, and its water-retaining properties help clay hold onto nutrients such as nitrogen.