Espoma Flower-tone 3-4-5 Blossom Booster is a premium flower food that is low in nitrogen and higher in phosphorous and potassium to maintain good plant growth and promote blooms rather than heavy foliage. Flower-tone's natural organics breakdown gradually providing a safe, long lasting food reservoir activated throughout the growing season. Flower-tone's all natural formula contains Bio-tone®, a proprietary blend of beneficial microbes. Bio-tone biologically enhances natural plant food to ensure superior plant growth.