Vermicrop Organics PK Boost Super Flower Fertilizer (1-13-6) is a complete organic fertilizer for heavy fruit, flower and vegetable varieties. This mixture of seabird guano, fishbone meal, kelp meal and potassium sulfate is unequaled in its purity and consistency. Phosphorus and potassium are very important and quickly depleted in the intense flowering cycles of prize-winning plants. PK Boost helps heavy-fruiting plants achieve their full potential. For best results, use with VermiBloom depending on flowering stage and plant variety.