Hesi PK supplies the large amounts of Phosphorus and Potassium your flowers need to release their maximum blooming potential. The blooming phase is the point when a plant's metabolism is working at full power.Hesi PK supplies the large amounts of Phosphorus and Potassium your flowers need to release their maximum blooming potential. The blooming phase is the point when a plant's metabolism is working at full power and large quantities of enzymes are being produced for flowering. Hesi PK is just the fuel they need to blast them through with ultimate blooming results.