This Osmocote fertilizer blend contains nitrogen (19%), phosphorus (5%), and potassium (8%) along with high amounts of magnesium (1.5%) and sulfur (8.1%). Osmocote fortifies this fertilizer with STEP Hi-Mag micronutrients. This slow-release fertilizer is water-soluble. Each bag contains 50 pounds of fertilizer. Osmocote 19-5-8 is great for general purpose outdoor production. It offers a consistent release over 8 to 9 months and across a wide range of temperatures. Its dual-coated design reduces nitrogen leeching and decomposes with minimal environmental impact. You can incorporate 19-5-8 directly into the growing media or apply it as a top dress. See application rates below. Osmocote designed this fertilizer to be both effective and affordable. It delivers nutrients in a highly efficient manner. This process results in robust growth and maximum yields.