Agron. Cristino Alberto Gómez L.
Fondo Grande Ahead

Soil Organic Matter
• Soil is not a simple substrate but an ecologic system in constant evolution.
• Organic agriculture tries to feed the organisms that are in the soil (macro, meso and micro), which will facilitate the nourishments’ assimilation by the plants.
• The most efficient way to favor the soil organisms’ development and multiplication is the continuous organic matter application.

Soil Organic Matter
• The Soil Organic Matter (SOM) is composed by remainders of plants, animals and microorganisms, which transform in humus when decomposed.
• Humus contains Nitrogen, Phosphorus, Potassium,
Calcium and micronutrients.
• In cultivated soils, humus can be consumed very quickly (1-3 years), unless it is restituted in the soil.

Soil Organic Matter
• The most common practices to replace the organic matter that is absorbed by the crops, are:
– Soil coverage.
– Use of green fertilizers.
– Elaboration of organic fertilizers.
• This show is focused in the elaboration of organic fertilizers as a practice to enrich the soil.

Organic Fertilizers
• Organic fertilizers are the result of a decomposition process of the organic remainders, by the diverse organisms’ action.
• The remainders are transformed in assimilable nourishments to the plants.
• Organic fertilizers are rich in nourishments, and low cost because their raw material is generally found in the farm.

Organic Fertilizers
• There are several types of organic fertilizers which two are the most known:
– Bokashi : the organic matter is fermented by aerobic or anaerobic processes in presence of high populations of beneficial microorganisms that will enrich the soil.
– Compost : the organic matter is converted in a humus-rich, homogeneous mass.

Bokashi
• The word “bokashi” means fermented organic fertilizer, in
Japanese.
• It is traditionally used in Japan to improve the soil quality, because the bokashi:
– Increases the diversity of soil microorganisms.
– Improve the physical and chemical properties of soil.
– Provide the soil with nutrients for the crops.
– Reduces the development of malefic microbes.

Bokashi
• Bokashi is inoculated with beneficial microorganisms, whose activity eliminates the pathogenic microbes when increasing the temperature until 45-50°C, while an alcoholic fermentation occurs. Those conditions are unfavorable for the pathogens.
• An adequate handling must be given to assure that bokashi does not take developed populations of malefic microorganisms or harmful insects.

¿How the bokashi is prepared?
• Materials:
– It will depend on the available materials in the farm. A common and simple mixture is:
• Forest soil 2 parts
• Rice semolina
• Grinded coal
• Rice husk
• Hen dung
1 part
1 part
1 part
1 part
– The forest soil is mainly used in higher quantity because it is the source of microorganisms.

¿How the bokashi is prepared?
• Materials:
– Commercial leavenings, crude milk or serum can be used, as well, to favor the fermentation.
• Preparation:
– The materials are colocated in layers, forming knolls, within a sheltered place.
– The materials are wet until a 30-40% and well mixed.
– The mixture is covered with bags, straw or another coverage.

¿How the bokashi is prepared?
• Cares:
– In anaerobic conditions, the mixture is fermented very quickly, reason why it is necessary to avoid the over warming.
– Temperature must be kept between 35 and 50°C, reason why a frequent reviewing is required.
– If the bokashi is warmer than 50°C, it can be regulated by mixing to oxygenate, and if needed, the mixture is extended.

¿How the bokashi is prepared?
• Cares:
– The fermentation process spend 7 to 30 days, depending on the materials.
– The bokashi will be ready when it gives off a pleasant scent to fermented and has colonies of white fungi in the surface.
– If the given off scent is like scent is to rotted, instead of fermented, then the process has not been successful.

¿How the bokashi is prepared?
• Cares:
– It is recommendable to use the bokashi as soon as possible, once it is ready.
– Bokashi must not be applied in contact with plants, because it is in process and the temperature can increase, affecting the plants.
– If it is necessary to store bokashi, it must be well dried, dispersed in cement under shade, and placed in a plastic bag.

Compost
• Compost is an organic fertilizer, whose main objective consists in to provide the soil with organic matter in advanced decomposition state, that aports available nourishments to the plants.
• During the compostage process, the nourishments get easy to absorb, and the pathogenic microorganisms that can affect the crop are eliminated.
• Compostage is a process, in presence of bacteria and fungi that favor the decomposition.

How the compost is elaborated?
• Materials:
– Most important it will be to be able to make it using the resources available in the farm, some of which can be:
• Dark soil
• Vegetable remainders (cacao rind, kitchen waste, etc.)
• Dung (of cows, goats, pigs, poultries, etc.)
• Lime or ash
• Water

How the compost is elaborated?
• Preparation:
– To choice a place close to where the materials will be obtained from, in order to facilitate the compost handling.
– It is recommendable to put a roof and to drain around the compost to avoid the water incidence when it rains.
– To prick the organic materials well to accelerate the decomposition.

How the compost is elaborated?
• Preparation:
– To collocate the materials in alternated layers, until forming a knoll of 1 – 1.20 m height.
– In each series, it will be first collocated the dark soil layer (10 cm.), followed by the vegetable remainders (20 cm), the dung and later the lime or ash
(dusted) and water.
Soil
Dung
Green matter
Soil
Dung
Green matter
Soil
Ash
1 m

How the compost is elaborated?
• Compost must be turned each 7-15 days depending on how much it gets warm during the process.
• Temperature must be reviewed daily to avoid that it goes up to 65-70°C.
• Compost will be ready approximately three months after beginning.

Compost ready to use

C. A. G. L.