Kanuma Soil Mix Component Plant Culture PHKanuma is the soil from the Kanuma region of Japan. Kanuma is mined from the ground then baked and sifted to size. Kanuma is excellent at retaining moisture and also promotes great drainage. Kanuma also allows roots to grow through it which helps create a fibrous root ball. Product properties: Excellent drainage properties. Very good against root rot after repotting plants Good drainage properties for air allows oxygen to get to the plant roots