Organic fertilizers are mostly made from animal or vegetable waste. Examples of some natural organic fertilizers would be manure, slurry, worm castings, peat, seaweed, humic acid, and guano. Processed organic fertilizers include compost, blood meal, bone meal, amino acids, seaweed extracts, natural enzyme-digested proteins, fish meal, and feather meal. Decomposing crop residue (green manure) from prior years is another source of fertility.
Organic fertilizers have a lot of advantages. Insoluble Nitrogen constitutes most of the nitrogen-supplying organic fertilizers and they act as slow-release fertilizers. Organic fertilizers release nutrients only when the soil is warm and moist, which tends to correspond with your plants’ times of greatest need. However, they rely on soil organisms to break down organic matter, so nutrients are released more slowly than they are from inorganic fertilizers. These organic fertilizers increase physical and biological nutrient storage mechanisms in soils, eventually mitigating risks of over-fertilization. Several types of slow-release nitrogen are used in the fertilizer, and differing amounts can be mixed with standard nitrogen sources to regulate how much is released and at what rate.
It must also be noted that than the inorganic fertilizers, the nutrient content, solubility, and nutrient release rates are typically much lower in organic fertilizers.
These fertilizers also help in Mobilizing existing soil nutrients, so that good growth is achieved with lower nutrient densities while wasting less when this is used in a garden. They also provide an edge by helping to retain soil moisture, eventually reducing the stress due to temporary moisture. They also help in building the soil structure, and prevent soil erosion, which all leads up to better vegetation. Like inorganic fertilizers, the frequency in which organic fertilizers are used is also less, making it convenient.
Apart from these, it must also be noted that Organic fertilizer may also build up concentrations of some nutrients, but buildup of toxicity is unlikely as long as the organic material is able to fully decompose. In addition, because organic fertilizers are made from natural sources, only limited amounts of fossil fuels are used in production. Like in some cases, use of chemical fertilizers can cause the plant to burn; however, this isn’t possible with the use of organic fertilizers. Organic fertilizers in comparison to its inorganic counterparts, have lesser health impact as well since they are phosphate free.
Some people are reluctant to use organic fertilizers; however, the time is not too far when people may have to use them out of sheer necessity since native sources, crude oil for example, of commercial fertilizers are diminishing rapidly.