Compost contains a full spectrum of essential plant nutrients.
- Compost contains macro and micronutrients often absent in synthetic fertilizers.
- Compost releases nutrients slowly,over months or years, unlike synthetic fertilizers
- Compost enriches soil and retains fertilizers better. Less fertilizer runs off to pollute waterways.
- Compost buffers the soil, neutralizing both acid & alkaline soils, bringing pH levels to the optimum range for nutrient availability to plants.
Compost helps bind clusters of soil particles, called aggregates, which provide good soil structure.
- Compost helps sandy soil retain water and nutrients.
- Compost loosens tightly bound particles in clay or silt soil so roots can spread, water drain & air penetration.
- Compost alters soil structure, making it less likely to erode, and prevents soil spattering on plants and thus prevents spreading disease.
- Compost can hold nutrients tight enough to prevent them from washing out, but loosely enough so plants can take them up as needed.
- Compost makes any soil easier to work on.
The basic principals in the production of compost
As the production of compost is considered as biological process so it is influenced by some environmental factors, each of these factors has the potential to significantly affect the composting process such as Aeration, Temperature, Moisture Content, Carbon: Nitrogen Ratio (C:N) of the organic materials involved in the process.
First: Components of Organic Materials
Necessary mixing various organic materials to get a good quality of compost containing most of the nutrients within 3-6 months of preparation of compost piles.
The most important element must be concentrated in the organic matter is the nitrogen and the carbon as carbon is the energy source to activate micro-organisms and nitrogen is necessary for protein synthesis to feed the organisms.
The ideal C: N ratio for composting is 20/30:1
Sources of Carbon found in dry straw while Nitrogen is found in grass clippings, plant trimmings and animals manure.
Each Micro-organism need oxygen to permit to make its function to sustain microbial activity inside the compost piles.
Oxygen renewal can be accomplished by moving the particles to a new position to expose them to new air by turned windrows.
Anaerobic conditions will set in if we do not turn the windrows and make good aeration which causes bad odors due to production of methane gas, H2S and ammonia.
Heat generated by microorganisms, as they decompose organic material, increases compost pile temperatures to be 60-70°C which increase in the first three days resulting from microbial activity, then temperature is kept inside the compost pile due to the thermal insulation property of most of the reactants.
Benefits of High Temperatures
- kill weed seeds
- kill insects and harmful germs
- Ideal temperature to accelerate decomposition process is between 35-60 degree while over 60 leads to drying organisms, aeration by continuous turned windrows is the only solution to retain ultimate temperature.
- Usually temperature rises if nitrogen percentage increases, therefore we add straw to increase carbon.
Fourth: Moisture content
The optimum percentage of moisture content is 50-60% to sustain microbial activity.
Increasing moisture percentage, will lead to delay air movement inside compost piles and reduce the speed of unwanted anaerobic decomposition.
Materials used in the construction of compost piles
- Animals and birds manure and (nitrogen source)
- Dry herbs, hay and straw (carbon source)
- Agriculture residues (plant trimmings) and crop residues (nitrogen source)
- Sawdust and wood materials (carbon source)
- Kitchen waste (carbon and nitrogen source)