SOIL TYPES AND THEIR MICROFLORA · Soil types are classified according to many more factors. · Soils are classified on the basis of Colour, Depth, pH, Geology (Study of Earth science), Productivity, Texture and Process of formation (Weathering). Soil types according to Depth · Soil types according to depth are as follows: a) Shallow soil - Soil depth less than 22.5 cm. Only shallow rooted crops are grown in such soil (e.g.) Paddy. b) Medium deep soil - Soil depth is 22.5 to 45 cm. Crops with medium deep roots are grown in this type of soil (e.g.) Sugar cane, Banana, Blackgram and Greengram. c) Deep soil - Soil depth is more than 45cm. Crops with long and deep roots are grown in this type a soil (e.g.) Mango and Coconut. Soil types according to Geology · Geologically, Indian soils can broadly be divided into soils of peninsular India and soils of extra-peninsular India. a) Soils of Peninsular India or Sedentary soils - T