Akadama(赤玉) the name of which comes from the Japanese words for red and ball, is a naturally occurring, granular clay like mineral that is used as soil for bonsai trees and other container-grown plants. It is surface mined, immediately sifted and bagged, and supplied in various grades: the deeper mined grade being somewhat harder and more useful in horticulture than the more shallow mined grades. Akadama may also act as one component of growing medium when combined with other elements such as sand, composted bark, peat, or crushed lava. Akadama’s colour darkens when moist which can help the grower determine when to water a tree.