Blossom Blaster? is a powerful blend of phosphorous and potassium fertilizers. Use Blossom Blaster? to add size to your blossoms by adding it to your nutrient solution just before flowers are starting to form. It supplies the plant with a reliable source of nutrition in the area where blossoms are developing. Blossom Blaster? gives high performance in all mediums. Use only 2x during flowering cycle. Use only with change of nutrient. 20 gm is sold in increments of 15 only.