What Is an Organic Fertilizer?
Organic fertilizers are fertilizers made from biological resources such as animals, plants, and microorganisms.
Typical examples of organic fertilizers are fertilizers made from fishmeal and oil meal. Although they are basically made from organic materials, there are some fertilizers, such as poultry manure and plant ashes, that are inorganic but still fall under the category of organic fertilizers.
Uses of Organic Fertilizers
Organic fertilizers are used to replenish nutrients in the soil and to improve soil fertility. Organic fertilizers are characterized by their less immediate but more lasting effects.
As such, they have two uses: as a soil improver before crops are grown, or as an additive depending on how well the crops are growing. Both are easy to use because the process is simply mixing it into the soil or sprinkling it on top of the soil.
Types of Organic Fertilizers
Because there are different types of organic fertilizers, it is important to understand the characteristics of each and use them efficiently.
1. Oil Cake
Oil cake is the lees of soybeans or rapeseed from which oil is removed. Among organic fertilizers, oil cake is particularly rich in nitrogen, and also contains phosphoric acid and potassium.
2. De-fatted Rice Bran
Non-fat rice bran is the powder produced when brown rice is polished. It contains high levels of nitrogen, phosphoric acid, potassium, vitamins, and sugar.
3. Grass and Wood Ash
Grass ash is the ash produced after burning fallen leaves, dead grass, and other vegetation. In addition to being high in potassium, it also contains lime and phosphoric acid.
4. Chicken Manure
Chicken manure is a fertilizer made by drying, fermenting, and carbonizing chicken manure, also called poultry manure. It contains a good balance of nitrogen, phosphoric acid, and potassium, and is also rich in magnesium and calcium.
5. Fish Meal
Fishmeal is made by boiling fish, removing the water and oil, and then drying it into a powder. It is rich in nitrogen and phosphoric acid.
6. Bone Meal
Bone meal is made by pressurizing and steaming pig or chicken bones at high temperatures, then drying and grinding them. It is rich in phosphoric acid and also contains a small amount of nitrogen.
Characteristics of Organic Fertilizers
1. Advantages
Highly Sustainable
Organic fertilizers are more persistent than chemical fertilizers because they are absorbed by plant roots after being decomposed by microorganisms. Therefore, organic fertilizers work slowly and remain effective for a long period.
Improved Soil Environment
The use of organic fertilizers activates useful microorganisms in the soil. The activation of useful microorganisms promotes soil compaction, which in turn improves soil aeration, water retention, drainage, and fertilizer retention. The use of organic fertilizers improves the soil environment and creates a suitable soil environment for crop cultivation.
Trace Essential Elements Can Be Expected to Be Supplied
Trace essential elements for plants include copper and zinc. Organic fertilizers contain a variety of elements, so the use of organic fertilizers can be expected to supply these trace essential elements.
2. Disadvantages
Low Immediate Effect
Organic fertilizers are broken down by microorganisms in the soil, and as a result, they are converted into nutrients that plants can absorb. Therefore, organic fertilizers do not have an immediate effect, and it takes time for their effects to become apparent.
Difficult to Adjust the Amount
Organic fertilizers are effective through the action of microorganisms, so their effectiveness may vary depending on the degree of activation of the microorganisms. Specifically, in an environment where microorganisms are easily activated, decomposition can easily proceed and a great effect can be expected.
On the other hand, in an environment where microorganisms are not easily activated, the effect may be small. Compared to chemical fertilizers, organic fertilizers are characterized by the difficulty in adjusting the amount according to the purpose.
They Can Cause Gas and Odors
Organic fertilizers are decomposed by microorganisms in the soil and transformed into nutrients that plants can absorb. It is important to note that gases and odors may be produced during this process. Specifically, gases can cause damage to plant roots, and strong odors can attract insects and birds.