Pure, untreated, raw fibrous Coconut Coir that is compressed into light convenient blocks that quickly expand into an amazing grow medium when you add water. OMRI listed for organic production. Coconut Coir has tremendous water retention capabilities that both save water and gives you added flexibility in watering frequency. Each block is ~11 lbs and yields ~15 gallons of growing media. Fully hydrated blocks will approximately fill an average wheelbarrow.