Characteristics of compost
In addition to providing nutrients for plants, compost works by improving the physical, chemical and biological structure of the soil. Physically, compost increases the ability of the soil to store water as a reserve in times of drought. Compost also makes the soil loose and is suitable for growing roots of plants. Even on sand-type soils, compost is used as an adhesive so that the soil becomes more solid. Whereas on clay or clay, compost functions to loosen the soil so it is not too solid.
Chemically, compost can increase the cation exchange capacity in the soil. According from Academics Research Education, because the more organic content in the soil, the better the cation exchange capacity. The cation exchange capacity functions to release important elements so that they can be absorbed easily by plants.
Biologically, compost is a good medium for soil organisms to multiply.
Whether it's from the type of microorganisms and other soil animals. Microorganism and soil animal activities will enrich the soil with important nutrients for plants.
A good compost has the following general characteristics: (1) It smells the same as the soil, does not smell bad, (2) The color is blackish brown, in the form of loose granules like soil, (3) If put in water completely sinks, and the water still clear does not change color, (4) If applied to the ground does not trigger the growth of weeds.
a. Compost forming process.
Any type of organic material will naturally experience weathering and decomposition by hundreds of types of microorganisms (bacteria, fungi, yeast) and other soil animals. The decomposition process goes with aerobic and anaerobic reactions one after another.
In the aerobic process, during the composting process there is no foul odor and will release energy in the form of heat. The increase in temperature due to heat released is very beneficial for the aerobic microbial environment. However, if the heat exceeds 65oC, most microbes will die and the composting process is slow. So it is necessary to decrease the temperature by stirring or reversing.
In the anaerobic process the reaction is gradual. The first stage, several types of facultative bacteria will break down organic matter into fatty acids. Then followed by the second stage, where other microbial groups will convert fatty acids into ammonia, methane, carbon dioxide and hydrogen.
The heat generated in the anaerobic process is lower than that of aerobics.
In general, the composting stage is divided into three phases. The first phase is the decomposition of organic material that is easily decomposed, produces high heat and lasts briefly. Then followed by the second phase, decomposition of organic materials that are difficult to decompose. Both phases produce fresh compost. Then the third phase is the maturation of compost into a humus-clay complex bond which results in the form of mature compost. Characteristics, odorless, crumb, blackish color, contain nutrients and have the ability to bind water.
b. Compost fertilizer. Compost raw material can be taken from the remains of plants and / or animal waste. Each ingredient contains different elements. These elements function as nutrients needed by plants.
Before making compost, we should know the purpose of fertilization first. We must know what substances are most needed by the plants we are caring for. For example, a newly growing plant needs more nitrogen (N), while plants that will bear fruit need more potassium (K).
After we know the purpose of fertilizing, then what kind of compost is determined?
Compost fertilizer is not like synthetic chemical fertilizer, where the nutrient contained in fertilizer is clearly the composition. In the compost, nutrients needed by plants are available in different compositions. Its composition depends on the raw material used.
Even so, we can make compost with nutrient composition that is tailored to the needs. We can make it by using a raw material approach. Each organic material has a specific content element. For example, straw, forage and chicken manure have a large N content. Well, we can make these materials compost that is rich in N elements.