Roots Organics HPK liquid bloom booster features a combination of seabird guano and phosphate rock, renowned as unparalleled reserves of available phosphorus, combined with langbeinite, a powerful source of potassium and magnesium that is carefully mined from ancient sea beds in the desert of the American Southwest. Aurora Innovations has taken generations of gardening experience and distilled it into a distinctive, easy-to-use formula for the home and professional gardener. Roots Organics HPK is minimally processed to preserve all the benefits and amazing synergistic qualities found in our exceptional ingredients.