Organic fertilizers largely comprise a variety of mined rock minerals, plant-derived materials that range from fresh or dried plant material to animal manures and litters to agricultural by-products. Bagged organic compost has a mixture of organic ingredients including manure, food scraps, and leaf mold.
Some organic fertilizers are manure using droppings from livestock, worms, bats, and seabirds. Organic fertilizers are also derived from animal matter such as such as Bone Meal , Fish meal etc.
While inorganic, or synthetic, fertilizers may contain some organic ingredients, the main difference is that they act quickly to simply feed the plant without actually enriching the soil, and may contribute to a toxic buildup of salts in the soil when over applied.