Miracle-Gro Shake 'n Feed Continuous Release Plant Food with Calcium for Tomatoes, Fruits, and Vegetables, 1-Pound (Slow Release Plant Fertilizer) Contains calcium for better quality fruits and vegetables Specially formulated with micronutrients to help plants grow strong, produce more fruits and vegetables Feeds up to 3 months Calcium helps prevent disorders in edible crops such as blossom-end rot, bitter pit, fruit cracking (commonly associated with calcium-deficiency) Ideal for both in-ground and container plants