Vermiculite
From Gardenology.org - Plant Encyclopedia and Gardening Wiki
Jump to navigationJump to searchVermiculite is a magnesium-aluminum-iron silicate with a high capacity for holding both water and nutrients. It's extremely light, and looks similar to mica, consisting of stacked layers.
It is often used in potting soil for plants that don't mind a fair amount of water because it can retain water and nutrients.
