The Sunleaves Classic Coir Block is a compressed coconut-fiber growing medium that expands to approximately 2.5 cubic feet when soaked in water. This renewable resource retains air and moisture extremely well. Classic Coir is the original finely-shredded medium that growers have come to know and love and is a preferred choice among African violet enthusiasts. Its great for amending soil and soilless mixtures. Expanded contents will fill approximately 30 one-gallon nursery pots.