Bio-Max 99 Volcanic sand/soil/rocks

Bio-Max 99 : Volcanic Soil, Volcanic Sand and Volcanic Rock:
Volcanic Sand (火山沙) is a potting medium and soil amendment material, it has excellent drainage properties and can be mixed into potting soil to increase drainage and root aeration.
Volcanic Sand can be used for top dressing as mulching and prevention of soil hardening and splashing. It can also be used at the base of pots for improved drainage.

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