Roots Organics HPK liquid bloom booster is a specially extracted natural source of phosphorus and potassium. Bat Guano, which is renowned as an unparalleled source of available natural phosphorus was combined with langbeinite, which is a natural source of potassium mined from ancient sea beds in the desert of the American Southwest. Carefully collected from specific global sources, Roots Organics HPK is minimally processed to preserve all of the benefits and amazing synergistic qualities found in our exceptional ingredients.