red ball earth
Akadama, aka red ball earth, is a naturally occurring, a granular clay-like mineral used as soil for bonsai trees and other container-grown plants. The king of weak acidity, water retention, and breathability, made from volcanic ash and widely cultivated in Japan. Obvious discoloration after water absorption can help observe the degree of dry and wet soil and judge the watering cycle. Akadama's color darkens when moist which can help the grower determine when to water a tree.However, it is easy to cause soil compaction due to pulverization, so it is not recommended to use in large amounts.