Espoma Bulb-tone 3-5-3 Blub & Flower Food is a premium plant food formulated specifically for bulbs and tubers. It contains bone meal and other natural organics to meet the special nutritional needs of these plants. Bulb-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. Bulb-tone feeds slowly, safely, and will provide a long lasting food reservoir to ensure superior results.