This naturally occurring material expands into layers under heat to become a highly absorbent, lightweight additive to potting soils and soilless mixes. Its unique characteristics are sterile and neutral ph, which promotes faster root growth and improved anchorage to seedlings. Vermiculite absorbs and holds both moisture and nutrients in the root zone while ensuring consistent aeration. It is recommended for heavy soils and raised beds that may suffer soil compaction over time. When used alone it proves an ideal media for rooting cuttings of all kinds.