Vermiculite 3.5 Cubic Foot Bag

Vermiculite is mica heated to 1,400 degrees, expanding it into particles capable of holding much air, water and nutrients. The mineral itself contains potassium, magnesium and calcium available in slow release. It has an absorbent capacity for fertilizer and also buffering and oxygen exchange.

It is normally used in a 50/50 mix in hydroponics, sometimes adding coco peat for extra water holding ability. It can be mixed with soil to allow for better aeration of the medium.