Composting of organic waste. Processes that occur during composting. Pile not heating up

The art and science of composting

Introduction

The history of composting goes back centuries. The first written mention of the use of compost in agriculture appeared 4500 years ago in Mesopotamia, in the interfluve of the Tigris and Euphrates (present-day Iraq). All civilizations of the Earth have mastered the art of composting. The Romans, Egyptians, Greeks actively practiced composting, which is reflected in the Talmud, the Bible and the Koran. Archaeological excavations confirm that the Mayan civilization 2000 years ago was also engaged in composting.

Despite the fact that the art of composting has been known to gardeners since time immemorial, in the 19th century, when artificial mineral fertilizers became widespread, it was largely lost. After the end of the Second World War, agriculture began to use the results of scientific developments. Agricultural science recommended the use of chemical fertilizers and pesticides in all forms to increase productivity. Chemical fertilizers have replaced compost.

In 1962, Rachel Carson's book Silent Spring was published, dealing with the results of widespread abuse of chemical pesticides and other pollutants. This was the signal for public protest and a ban on the production and use of hazardous products. Many have begun to rediscover the benefits of so-called organic farming.

One of the earliest publications in this respect was Sir Albert Howard's An Agricultural Testament, published in 1943. The book sparked a huge interest in organic methods in agriculture and horticulture. Today, every farmer recognizes the value of compost in stimulating plant growth and in restoring depleted and lifeless soil. How would the rediscovery of this ancient agricultural art.

Organic farming cannot be called a complete return to the old, since it has all the achievements of modern science at its disposal. All chemical and microbiological processes occurring in the compost heap have been thoroughly studied, and this makes it possible to consciously approach the preparation of compost, regulate and direct the process in the right direction.

Compostable waste ranges from urban waste, which is a mixture of organic and inorganic components, to more homogeneous substrates such as animal and crop waste, raw activated sludge and sewage. Under natural conditions, the process of biodegradation proceeds slowly, on the surface of the earth, at ambient temperature and, predominantly, under anaerobic conditions. Composting is a way to accelerate natural degradation under controlled conditions. Composting is the result of understanding the operation of these natural biological and chemical systems.

Composting is an art. This is how the exceptional importance of compost for the garden is now assessed. Unfortunately, we still pay very little attention to the proper preparation of compost. And properly prepared compost is the basis, the guarantee of the future harvest.
There are well-established and proven general principles for making compost.

1. Theoretical foundations of the composting process

The composting process is a complex interaction between organic waste, microorganisms, moisture and oxygen. Waste usually has its own endogenous mixed microflora. Microbial activity increases when the moisture content and oxygen concentration reach the required level. In addition to oxygen and water, microorganisms need sources of carbon, nitrogen, phosphorus, potassium and certain trace elements for growth and reproduction. These needs are often met by the substances contained in the waste.

By consuming organic waste as a food substrate, microorganisms multiply and produce water, carbon dioxide, organic compounds and energy. Part of the energy obtained during the biological oxidation of carbon is consumed in metabolic processes, the rest is released in the form of heat.

Compost as the end product of composting contains the most stable organic compounds, decay products, biomass of dead microorganisms, a certain amount of live microbes and products of chemical interaction of these components.

1.1. Microbiological aspects of composting

Composting is a dynamic process that occurs due to the activity of a community of living organisms of various groups.

The main groups of organisms involved in composting are:
microflora - bacteria, actinomycetes, fungi, yeast, algae;
microfauna - protozoa;
macroflora - higher fungi;
macrofauna - bipedal centipedes, mites, springtails, worms, ants, termites, spiders, beetles.

Many species of bacteria (more than 2000) and at least 50 species of fungi take part in the composting process. These species can be subdivided into groups according to the temperature intervals in which each of them is active. For psychrophiles, the preferred temperature is below 20 degrees Celsius, for mesophiles - 20-40 degrees Celsius and for thermophiles - over 40 degrees Celsius. The microorganisms that dominate the last stage of composting are usually mesophiles.

Although the number of bacteria in the compost is very high (10 million - 1 billion mc/g of wet compost), due to their small size they make up less than half of the total microbial biomass.

Actinomycetes grow much more slowly than bacteria and fungi and do not compete with them in the early stages of composting. They are more noticeable in later stages of the process, when they become very numerous, and the white or gray coating, typical of actinomycetes, is clearly visible at a depth of 10 cm from the surface of the composted mass. Their number is lower than the number of bacteria and is about 100 thousand - 10 million cells per gram of wet compost.

Fungi play an important role in the degradation of cellulose, and the condition of the compost mass must be controlled in such a way as to optimize the activity of these microorganisms. Temperature is an important factor, as mushrooms die if it rises above 55 degrees Celsius. After a decrease in temperature, they again spread from colder zones throughout the volume.

Not only bacteria, fungi, actinomycetes, but also invertebrates take an active part in the composting process. These organisms coexist with microorganisms and are the basis of the "health" of the compost heap. The friendly team of composters includes ants, beetles, centipedes, caterpillars of the winter cutworm, false scorpions, fruit beetle larvae, centipedes, mites, nematodes, earthworms, earwigs, wood lice, springtails, spiders, haymaker spiders, enchitriids (white worms), etc. .. After reaching the maximum temperature, the compost, cooling down, becomes available to a wide range of soil animals. Many soil animals contribute greatly to the recycling of compostable material through its physical crushing. These animals also contribute to the mixing of different components of the compost. In temperate climates, earthworms play a major role in the final stages of the composting process and further incorporation of organic matter into the soil.

1.1.1. Composting stages
Composting is a complex, multi-stage process. Each of its stages is characterized by different consortiums of organisms. The composting phases consist of (Figure 1):
1. lag phase (lag phase),
2. mesophilic phase (mesophilic phase),
3. thermophilic phase (thermophilic phase),
4. maturation phase (final phase).

FIGURE 1. STAGES OF COMPOSTING.

Phase 1 (lag phase) begins immediately after the introduction of fresh waste into the compost heap. During this phase, the microorganisms adapt to the type of waste and living conditions in the compost heap. The decay of waste begins already at this stage, but the total population of microbes is still small, the temperature is low.

Phase 2 (mesophilic phase). During this phase, the process of degradation of the substrates intensifies. The number of microbial populations increases mainly due to mesophilic organisms that adapt to low and moderate temperatures. These organisms rapidly degrade soluble, easily degradable components such as simple sugars and carbohydrates. The reserves of these substances are quickly depleted, microbes begin to decompose more complex molecules, such as cellulose, hemicellulose and proteins. After consumption of these substances, microbes secrete a complex of organic acids, which serve as a food source for other microorganisms. However, not all organic acids formed are absorbed, which leads to their excessive accumulation and, as a result, to a decrease in the pH of the medium. pH serves as an indicator of the end of the second stage of composting. But this phenomenon is temporary, since an excess of acids leads to the death of microorganisms.

Phase 3 (thermophilic phase). Temperature rises as a result of microbial growth and metabolism. When the temperature rises to 40 degrees Celsius and above, mesophilic microorganisms are replaced by microbes that are more resistant to high temperatures - thermophiles. When the temperature reaches 55 degrees Celsius, most human and plant pathogens die. But if the temperature exceeds 65 degrees Celsius, the aerobic thermophiles of the compost pile will also die. Due to the high temperature, there is an accelerated breakdown of proteins, fats and complex carbohydrates such as cellulose and hemicellulose - the main structural components of plants. As a result of the exhaustion of food resources, metabolic processes decline, and the temperature gradually decreases.

Phase 4 (final phase). As the temperature drops to the mesophilic range, mesophilic microorganisms begin to dominate in the compost heap. Temperature is the best indicator of the onset of the ripening stage. In this phase, the remaining organic substances form complexes. This complex of organic substances is resistant to further decomposition and is called humic acids or humus.

1.2. Biochemical aspects of composting

Composting is a biochemical process designed to convert solid organic waste into a stable, humus-like product. Simplified, composting is the biochemical breakdown of the organic constituents of organic waste under controlled conditions. The application of control distinguishes composting from the naturally occurring processes of putrefaction or decomposition.

The composting process depends on the activity of microorganisms that need a carbon source for energy and cell matrix biosynthesis, as well as a nitrogen source for the synthesis of cellular proteins. To a lesser extent, microorganisms need phosphorus, potassium, calcium and other elements. Carbon, which makes up about 50% of the total mass of microbial cells, serves as an energy source and building material for the cell. Nitrogen is a vital element in the cell's synthesis of proteins, nucleic acids, amino acids, and enzymes necessary for building cellular structures, growth, and function. The need for carbon in microorganisms is 25 times higher than for nitrogen.

In most composting processes these requirements are met by the initial composition of organic waste, only the carbon to nitrogen ratio (C:N) and, occasionally, the level of phosphorus may need to be adjusted. Fresh and green substrates are rich in nitrogen (so-called "green" substrates), while brown and dry (so-called "brown" substrates) are rich in carbon (Table 1).

TABLE 1.
RATIO OF CARBON AND NITROGEN IN SOME SUBSTRATES.

For the formation of compost, the carbon-nitrogen balance (C:N ratio) is of great importance. The C:N ratio is the ratio of the weight of carbon (but not the number of atoms!) to the weight of nitrogen. The amount of carbon needed far outweighs the amount of nitrogen. The reference value for this ratio in composting is 30:1 (30 g of carbon per 1 g of nitrogen). The optimal C:N ratio is 25:1. The more the carbon-nitrogen balance deviates from the optimum, the slower the process proceeds.

If the solid waste contains a large amount of carbon in fixed form, then the acceptable carbon-nitrogen ratio may be higher than 25/1. A higher value of this ratio leads to the oxidation of excess carbon. If this indicator significantly exceeds the specified value, the availability of nitrogen decreases, and microbial metabolism gradually fades. If the ratio is less than optimal, as is the case in activated sludge or manure, nitrogen will be removed as ammonia, often in large quantities. The loss of nitrogen due to volatilization of ammonia can be partially replenished due to the activity of nitrogen-fixing bacteria, which appear mainly under mesophilic conditions in the late stages of biodegradation.

The main detrimental effect of a too low C/N ratio is the loss of nitrogen through the formation of ammonia and its subsequent volatilization. Meanwhile, nitrogen retention is very important for compost formation. The loss of ammonia becomes most noticeable during high-speed composting processes, when the degree of aeration increases, thermophilic conditions are created and pH reaches 8 or more. This pH value favors the formation of ammonia, and the high temperature accelerates its volatilization.

The uncertainty in the amount of nitrogen loss makes it difficult to accurately determine the required initial C:N value, but in practice it is recommended in the range of 25:1 - 30:1. At low values of this ratio, the loss of nitrogen in the form of ammonia can be partially suppressed by the addition of excess phosphates (superphosphate).

During the composting process, there is a significant reduction in the ratio from 30:1 to 20:1 in the final product. The C:N ratio is constantly decreasing, because during the absorption of carbon by microbes, 2/3 of it is released into the atmosphere in the form of carbon dioxide. The remaining 1/3, together with nitrogen, are included in the microbial biomass.

Since the weighing of the substrate is not practiced during the formation of the compost heap, the mixture is prepared from equal parts of the "green" and "brown" components. Regulation of the ratio of carbon and nitrogen is based on the quality and quantity of a particular type of waste that is used when laying the heap. Therefore, composting is considered an art and a science at the same time.

Calculation of the ratio of carbon to nitrogen (C:N)

There are several ways to calculate the ratio of carbon to nitrogen. We give the simplest, taking manure as a sample. The organic matter of semi-rotted and rotted manure contains approximately 50% carbon (C). Knowing this, as well as the ash content of manure and the total nitrogen content in it in terms of dry matter, the C:N ratio can be determined using the following formula:

C:N = ((100-A)*50)/(100*X)

Where A is the ash content of manure,%;
(100 - A) - content of organic matter, %;
X is the content of total nitrogen per absolutely dry weight of manure, %.
For example, if the ash content A = 30%, and the content of total nitrogen in manure = 2%, then

C:N = ((100-30)*50)/(100*2) = 17

1.3. Critical composting factors

The process of natural decomposition of the substrate during composting can be accelerated by controlling not only the ratio of carbon and nitrogen, but also humidity, temperature, oxygen levels, particle size, size and shape of the compost heap, pH.

1.3.1. Nutrients & Supplements

In addition to the above substances necessary for the growth and reproduction of microorganisms - the main decomposers of organic waste, various chemical, herbal and bacterial additives are used to increase the rate of composting. With the exception of the possible need for additional nitrogen, most waste contains all the necessary nutrients and a wide range of microorganisms, making it compostable. Obviously, the onset of the thermophilic stage can be accelerated by returning some of the finished compost to the system.

Carriers (wood chips, straw, sawdust, etc.) are usually needed to maintain a structure that provides aeration when composting wastes such as raw activated sludge and manure.

1.3.2. pH

PH is the most important indicator of the "health" of a compote pile. As a rule, the pH of household waste in the second phase of composting reaches 5.5–6.0. In fact, these pH values are an indicator that the composting process has begun, that is, it has entered the lag phase. The pH level is determined by the activity of acid-forming bacteria, which decompose complex carbon-containing substrates (polysaccharides and cellulose) into simpler organic acids.

The pH values are also maintained by the growth of fungi and actinomycetes capable of degrading lignin in an aerobic environment. Bacteria and other microorganisms (fungi and actinomycetes) are capable of decomposing hemicellulose and cellulose to varying degrees.

Microorganisms that produce acids can also utilize them as their sole source of nutrition. The end result is an increase in pH to 7.5-9.0. Attempts to control pH with sulfur compounds are ineffective and impractical. Therefore, it is more important to manage aeration by controlling anaerobic conditions, recognizable by fermentation and putrid odor.

The role of pH in composting is determined by the fact that many microorganisms, like invertebrates, cannot survive in a very acidic environment. Fortunately, pH is usually controlled naturally (carbonate buffer system). Be aware that if you decide to adjust the pH by neutralizing acid or alkali, this will result in salt formation, which can have a negative impact on the health of the pile. Composting proceeds easily at pH values of 5.5–9.0, but is most effective in the range of 6.5–9.0. An important requirement for all components involved in composting is low acidity or low alkalinity at the initial stage, but mature compost should have a pH in the range close to neutral pH values (6.8–7.0). In the event that the system becomes anaerobic, the accumulation of acid can lead to a sharp decrease in pH to 4.5 and a significant limitation of microbial activity. In such situations, aeration becomes the lifeline that will return the pH to acceptable values.

The optimal pH range for most bacteria is between 6-7.5, while for fungi it can be between 5.5 and 8.

1.3.3. Aeration

Under normal conditions, composting is an aerobic process. This means that the presence of oxygen is necessary for the metabolism and respiration of microbes. Translated from Greek aero means air and bios- life. Microbes use oxygen more often than other oxidizing agents, since with its participation reactions proceed 19 times more vigorously. The ideal concentration of oxygen is 16 - 18.5%. At the beginning of composting, the concentration of oxygen in the pores is 15-20%, which is equivalent to its content in the atmospheric air. The concentration of carbon dioxide varies in the range of 0.5-5.0%. During composting, the concentration of oxygen decreases and carbon dioxide increases.

If the oxygen concentration drops below 5%, anaerobic conditions occur. Controlling the oxygen content of the outgoing air is useful for adjusting the composting regime. The easiest way to do this is by smell, as decomposition odors indicate the onset of an anaerobic process. Since anaerobic activity is characterized by bad smells, small concentrations of bad smelling substances are allowed. The compost heap acts as a biofilter, trapping and neutralizing malodorous components.

Some compost systems are able to passively maintain an adequate oxygen concentration through natural diffusion and convection. Other systems need active aeration, provided by blowing air or turning and mixing the compostable substrates. When composting wastes such as raw activated sludge and manure, carriers (wood chips, straw, sawdust, etc.) are usually used to maintain an aeration structure.

Aeration can be carried out by natural diffusion of oxygen into the compost mass by mixing the compost manually, using mechanisms or forced aeration. Aeration has other functions in the composting process. The air flow removes carbon dioxide and water produced during the life of microorganisms, and also removes heat through evaporative heat transfer. The oxygen demand changes during the process: it is low in the mesophilic stage, rises to a maximum in the thermophilic stage, and drops to zero during the cooling and ripening stage.

With natural aeration, the central areas of the composted mass may become anaerobiotic, since the rate of oxygen diffusion is too low for ongoing metabolic processes. If the compost-forming material has anaerobic zones, then butyric, acetic and propionic acids can be produced. However, the acids are soon used by bacteria as a substrate, and the pH begins to rise with the formation of ammonia. In such cases, manual or mechanical agitation allows air to enter the anaerobic areas. Stirring also contributes to the dispersion of large fragments of raw materials, which increases the specific surface area required for biodegradation. Controlling the mixing process ensures that most of the raw materials are processed under thermophilic conditions. Excessive mixing leads to cooling and drying of the composted mass, to breaks in the mycelium of actinomycetes and fungi. Mixing compost in heaps can be too costly in terms of machine and manual labor, and so the frequency of mixing is a compromise between economics and process needs. When using composting plants, it is recommended to alternate periods of active mixing with periods without mixing.

1.3.4. Humidity

Compost microbes need water. Decomposition proceeds much faster in thin liquid films formed on the surfaces of organic particles. 50-60% moisture is considered optimal for the composting process, but higher values are possible when carriers are used. The optimum moisture content varies and depends on the nature and size of the particles. A moisture content of less than 30% inhibits bacterial activity. At a moisture content of less than 30% of the total mass, the rate of biological processes drops sharply, and at a moisture content of 20% they may stop altogether. Humidity over 65% prevents air from diffusing into the pile, which greatly reduces degradation and is accompanied by stench. If the humidity is too high, the voids in the compost structure are filled with water, which limits the access of oxygen to microorganisms.

The presence of moisture is determined by touch when you click on a lump of compost. If, when pressed, 1-2 drops of water are released, then the moisture content of the compost is sufficient. Straw-type materials are resistant to high humidity.

Water is formed during composting due to the vital activity of microorganisms and is lost due to evaporation. In the case of forced aeration, water losses can be significant, and it becomes necessary to add additional water to the compost. This can be achieved by irrigation with water or by adding activated sludge and other liquid waste.

1.3.5. Temperature

Temperature is a good indicator of the composting process. The temperature in the compost heap begins to rise a few hours after the laying of the substrate and varies depending on the stages of composting: mesophilic, thermophilic, cooling, ripening.

During the cooling stage that follows the temperature peak, the pH slowly drops but remains alkaline. Thermophilic fungi from colder zones again capture the entire volume and, together with actinomycetes, consume polysaccharides, hemicellulose, and cellulose, breaking them down to monosaccharides, which can subsequently be utilized by a wide range of microorganisms. The rate of heat release becomes very low and the temperature drops to that of the environment.
The first three stages of composting proceed relatively quickly (in days or weeks) depending on the type of composting system used. The final stage of composting - maturation, during which the loss of mass and heat release are small - lasts several months. In this stage, complex reactions occur between lignin residues from the waste and proteins of dead microorganisms, leading to the formation of humic acids. Compost does not heat up, anaerobic processes do not occur during storage, it does not take nitrogen from the soil when it is introduced into it (the process of nitrogen immobilization by microorganisms). The final pH value is slightly alkaline.

High temperatures are often considered a prerequisite for successful composting. In fact, at too high a temperature, the biodegradation process is inhibited due to inhibition of the growth of microorganisms, very few species remain active at temperatures above 70 degrees Celsius. The threshold after which suppression occurs is a temperature of about 60 degrees Celsius, and therefore high temperatures for a long period must be avoided with rapid composting. However, temperatures in the order of 60 degrees Celsius are useful in controlling heat-sensitive pathogens. Therefore, it is necessary to maintain conditions under which, on the one hand, pathogenic microflora will die, and on the other hand, microorganisms responsible for degradation will develop. For these purposes, the recommended optimum temperature is 55 degrees Celsius. Temperature control can be achieved with forced ventilation during composting. Heat is removed by an evaporative cooling system.

The main factors in the destruction of pathogenic organisms during the formation of compost are heat and antibiotics produced by degrading microorganisms. The high temperature is maintained for a time sufficient for the death of pathogens.

The best conditions for compost formation are mesophilic and thermophilic temperature limits. Due to the many groups of organisms involved in the process of compost formation, the range of optimal temperatures for this process is generally very wide - 35-55 degrees Celsius.

1.3.6. Particle dispersion

The main microbial activity is manifested on the surface of organic particles. Consequently, a decrease in the particle size leads to an increase in the surface area, and this, in turn, would seem to be accompanied by an increase in microbial activity and decomposition rate. However, when the particles are too small, they stick together tightly, impairing air circulation in the pile. This reduces the supply of oxygen and significantly reduces microbial activity. Particle size also affects the availability of carbon and nitrogen. The allowable particle size is in the range of 0.3-5 cm, but varies depending on the nature of the raw material, the size of the pile and weather conditions. Optimum particle size is required. For mechanized plants with agitation and forced aeration, the particles can have a size after grinding of 12.5 mm. For immobile heaps with natural aeration, a particle size of the order of 50 mm is best.
It is also desirable that the raw materials for composting contain a maximum of organic material and a minimum of inorganic residues (glass, metal, plastic, etc.).

1.3.7. The size and shape of the compost heap

Various organic compounds present in the composted mass have different calorific values. Proteins, carbohydrates and lipids have a heat of combustion in the range of 9-40 kJ. The amount of heat released during composting is very significant, so that when composting large masses, temperatures of the order of 80-90 degrees Celsius can be reached. These temperatures are well above the optimum of 55 degrees Celsius and in such cases evaporative cooling via evaporative aeration may be necessary. Small amounts of compostable material have a high surface to volume ratio.

The compost heap should be of sufficient size to prevent rapid loss of heat and moisture and ensure effective aeration throughout. When composting material in heaps under natural aeration conditions, they should not be stacked more than 1.5 m in height and 2.5 m in width, otherwise the diffusion of oxygen to the center of the heap will be difficult. In this case, the heap can be extended into a compost row of any length. The minimum heap size is about one cubic meter. The maximum acceptable pile size is 1.5m x 1.5m for any length.

The stack can be of any length, but its height has a certain value. If the stack is too high, then the material will be compressed by its own weight, there will be no pores in the mixture, and the anaerobic process will begin. A low compost pile loses heat too quickly and cannot be kept at the optimum temperature for thermophilic organisms. In addition, due to the large loss of moisture, the degree of compost formation slows down. Empirically, the most acceptable heights of compost piles for any type of waste have been established.

Uniform decomposition is ensured by mixing the outer edges towards the center of the compost pile. At the same time, any insect larvae, pathogenic microbes or insect eggs are exposed to fatal temperatures for them inside the compost pile. If there is excess moisture, frequent stirring is recommended.

1.3.8. Free volume

The compostable mass can be simplistically considered as a three-phase system, which includes solid, liquid and gas phases. The structure of the compost is a network of solid particles, in which voids of various sizes are enclosed. The voids between the particles are filled with gas (mainly oxygen, nitrogen, carbon dioxide), water or a gas-liquid mixture. If the voids are completely filled with water, then this greatly complicates the transfer of oxygen. Compost porosity is defined as the ratio of free volume to total volume, and free gas space is defined as the ratio of gas volume to total volume. The minimum free gas space should be in the order of 30%.

The optimum moisture content of the composted mass varies and depends on the nature and fineness of the material. Different materials can have different moisture content as long as the appropriate amount of free gas space is maintained.

1.3.9. Compost maturation time

The time it takes for the compost to mature depends on the factors listed above. The shorter maturation period is associated with optimal moisture content, C:N ratio and frequency of aeration. The process is slowed down by insufficient substrate moisture, low temperatures, high C:N ratio, large substrate particle sizes, high wood content and inadequate aeration.
The process of composting raw materials proceeds much faster if all the conditions necessary for the growth of microorganisms are met. The optimal conditions for the composting process are presented in Table 2.

TABLE 2
OPTIMUM CONDITIONS FOR THE COMPOSTING PROCESS

The challenge is to implement a set of these parameters in the form of inexpensive but reliable composting systems.

The required duration of the compost formation process also depends on the environmental conditions. In the literature, you can find different values for the duration of composting: from several weeks to 1-2 years. This time ranges from 10-11 days (composting garden waste) to 21 days (waste with a high C/N ratio of 78:1). With the help of special equipment, the duration of this process is reduced to 3 days. With active composting, the duration of the process is 2–9 months (depending on the composting methods and the nature of the substrate), but a shorter period is also possible: 1–4 months.

During composting, the physical structure of the material undergoes a change. It takes on the dark color associated with compost. Noteworthy is the change in the smell of the composted material from fetid to the "smell of the earth" due to geosmin and 2-methylisoborneol, the waste products of actinomycetes.

The end result of the composting step is the stabilization of organic matter. The degree of stabilization is relative, since the final stabilization of organic matter is associated with the formation of CO2, H2O and mineral ash.

The desired degree of stability is that in which there are no problems when storing the product even when wet. The difficulty lies in determining this moment. The dark color typical of compost may appear long before the desired degree of stabilization is achieved. The same can be said about the "smell of the soil."

In addition to appearance and smell, stability parameters are: final temperature drop, degree of self-heating, amount of decomposed and stable substance, increase in redox potential, oxygen uptake, growth of filamentous fungi, starch test.

So far, unambiguous criteria have not been developed to assess acceptable levels of stability and "maturity" of the compost. Composting potential can be determined by assessing the rate of conversion of organic compounds into soil constituents and humus, which increase soil fertility.

Humus formation (humification) is a set of all processes involved in the transformation of fresh organic matter into humus. Determining the rate of this conversion is a complex task and, in turn, an important tool for the scientific study of the composting process.

From a number of works carried out by various researchers in this field, it becomes apparent that the parameters that can be used as indicators of the rate of humification, "maturity" and stability of composts fall into two categories. The first category - pH, total organic carbon (TOC), humification index (HI) and carbon to nitrogen ratio (C/N) - decrease during the composting period. Other chemical and humification parameters - total nitrogen content (TON), total extractable carbon (TEC) and humic acids (HA), ratio of humic acids to fulvic acids (HA:PhA), degree of humification (DH), humification rate (HR) , maturity index (MI), humification index (IHP) - increase over time, and the quality of composts stabilizes.

Among the analyzed chemical parameters, the ratio of humic acids to fulvic acids, the rate of humification, the degree of humification, the humification index, the maturity index, the humification index, the carbon to nitrogen ratio have so far been considered key parameters for assessing the rate and degree of conversion of organic waste during composting.

S.M. Tiquia has proposed a simpler approach to assessing the "maturity" of compost based on pig manure, the processing of which into a complete and safe organic fertilizer is an important agricultural and environmental problem. The universality of this approach should be emphasized. With its help, it is possible to evaluate not only the naturally occurring composting process in nature, but also carried out using biotechnological methods. The category of the latter includes vermicomposting with the help of dung worms, as well as the use of special microbial “starter cultures”.

Since composting is carried out due to the vital activity of the microbial community of manure, microbiological indicators were taken as indicators of the "maturity" of the compost. Of the six microbiological parameters studied, the test of dehydrogenase activity turned out to be the most informative and adequate. Compared to other criteria, it turned out to be a simpler, faster and cheaper method for monitoring the stability and readiness of the compost. Once the material is found to be stable enough for storage, it is sorted into fractions by screening.

Any garden or garden soil needs regular feeding. Own compost provides plant nutrition with environmentally friendly organic fertilizer that does not require costs. Special knowledge and skills for harvesting humus are not required, and the benefits for the garden are very tangible.

Homemade compost is an excellent source of organic nutrients. Compost is a product of the processing of organic material (waste) under the influence of a specific microclimate and microorganisms.

Many gardeners prefer to prepare the compost on their own, as this not only saves time and money, but also reduces the amount of hassle, which is always enough on the site. In order to understand from what and how to make fertilizer correctly, it is important to understand how the procedure for its formation takes place. In fact, composting is a natural process of decomposition of organic waste. In the process of fermentation, a fertile loose composition is obtained, which is suitable for any soil. The most common way to make compost with your own hands is to collect leftovers from the kitchen and organic garbage in one pile. After that, bacteria begin to work, which will process "yesterday's" borscht and fallen leaves into humus. As a rule, you can prepare compost in different ways, however, the whole process comes down to using the aerobic or anaerobic method.

Self-made humus is more profitable and healthier than a purchased mixture of unknown ingredients and brings a lot of benefits.

What is the benefit of making compost in the country?

Compost is considered one of the best fertilizers, which, when applied to the soil, fills it with a huge amount of trace elements.

Compost is the cheapest and most practical means for proper soil structuring, as it increases moisture conservation and creates loosening necessary for all plants.

Spreading compost over the surface of the soil creates the best organic mulch that will conserve moisture and inhibit the growth of many weeds in the area.

Composting in a summer cottage is a very useful process, as well as a significant contribution to the development and environmental protection. Not a single mineral fertilizer can be compared with high-quality compost, and a properly formed pit in which organic components rot can become a real incubator for beneficial bacteria and microorganisms.

Composting significantly reduces your physical effort, since now you do not need to take out a good part of the garbage from the territory of your summer cottage, everything can simply be placed in a special pit.

The use of a compost pit reduces the time and effort to remove a large part of the garbage (tops, plants, wood waste, etc.) from the summer cottage
Compost is an affordable means to improve the physical properties of the soil (structuring), as well as organic fertilizer
The uniform distribution of humus on the surface of the garden ensures moisture retention and inhibits the growth of weeds
The preparation of humus in the country is a natural process in which organic waste is disposed of, fertilizer is prepared and the environment is not harmed

What can be put in compost?

cut grass;
foliage that falls in autumn;
droppings of cattle and birds;
peat residues;
tea leaves and coffee;
egg shells, provided that they have not undergone heat treatment;
peel and remains of raw vegetables and fruits;
thin branches;
straw, sawdust and shells from seeds;
shredded paper or cardboard.

What not to put in compost:

vegetable peel after boiling or frying;
diseased leaves and branches;
weed plants;
citrus peel;

Thus, compost waste is divided into two types: nitrogenous (manure and bird droppings, grass, raw vegetables and fruits) and carbonaceous (fallen leaves, sawdust, finely shredded paper or cardboard).

When making your own compost heap, it is important to stick to a 5:1 ratio, i.e. most of it consists of brown components, which are the basis for feeding beneficial bacteria. One part of the pile is green waste. To speed up the process, shredded paper, corn and sunflower shoots, sawdust, dry leaves and grass are used as brown components.

Green components are essential for beneficial microbes, and they decompose quickly. The lack of green part can lead to a lengthening of the time required for composting. If you go too far with the green part, then the pile will smell unpleasantly of ammonia (rotten eggs). The remains of meat and fish products should not be included in the compost in the country, as they take longer to decompose, and there will be an unpleasant smell around.

How to do

The balance of the components is the golden rule at the stage when you are already ready to make garden "gold" in the country with your own hands. A properly stacked pile emits the smell of fertile soil, but if you hear an unpleasant smell, then you need to add brown residues. In order for the process of processing residues to start, the temperature in the center of the pile must reach 60-70 degrees. It should feel warm from it, but if it seems cool to the touch, then you need to add greenery.

The second important rule of a compost heap is constant moisture. It should be like a damp "rug", but not wet. If you notice that a crust is forming, then you need to add a little water. The aerobic composting process requires a constant supply of oxygen, so the pile must be turned frequently. The more often you turn the compost, the faster the finished fertilizer will ripen. You can properly prepare compost in the country in a fast and slow way. Beginning summer residents usually use the first option.

This requires a special box made of wood or plastic, where all the components will be laid. If there is no box, then you can use a pit with wooden logs.

The main thing is that oxygen can freely flow from above and to the side to the contents. Laying components in layers or at random is up to you.

Consider the option of laying a compost pit in layers:

Rigid materials should be well crushed, while soft materials, such as grass clippings, should be mixed with harder waste. These activities will achieve the optimal degree of looseness of the compost mass.
During the formation of the heap, the thickness of the layer of stacked waste should be 15 cm.
In the course of work, care must be taken not to form thick layers. Since in this case compaction will occur, which in turn will make the material impervious to moisture and air.
Dry raw materials in the preparation of compost should be slightly moistened, but not poured abundantly.
The size of the heap itself has a significant impact on maintaining optimal moisture and temperature indicators in the compost heap. In order for the pile to meet all the necessary requirements, its height should be from 1.2 to 1.5 m, and its length should also be 1.5 m.
Each layer must be sprinkled with lime. When forming a pile of 1.2x1.2 m of this substance, 700 g will be required. In addition to lime, components such as ammonium sulfate and superphosphate will also be needed - 300 g and 150 g, respectively.
An alternative to ammonium sulfate can be bird droppings (4.5 kg of droppings equates to 450 g of ammonium sulfate). When applying these additives, before laying each layer of waste, the soil layer must be loosened by about 1 cm. If desired, a small amount of lime can be replaced with wood ash. This will help to saturate the heap with potassium and reduce its acidity. To improve the quality of the compost and accelerate its maturation, you can water it with liquid manure.
Thus, by adding layers of waste, lime, superphosphate, ammonium sulfate and soil, the pile must be brought to a height of 1.2 m. When the required dimensions are reached, the pile should be covered with soil with a layer of up to 5 cm. her from the rain. To do this, you can use a film, a sheet of plastic or other material. The compost mass must be maintained in a damp state, watering it periodically with water.

Four stages of compost maturation

The first stage is decomposition and fermentation. Its duration is from 3 to 7 days. At this stage, the temperature in the heap increases significantly and reaches 68 °C.
In the second stage, called restructuring, the temperature drops. The reproduction of fungi and the formation of gases also enter the active phase. These processes take place over two weeks.
The third stage is characterized by the formation of new structures. After lowering the temperature level to 20 ° C, worms appear in the mass. The result of their presence is the mixing of mineral and organic substances. As a result of the vital activity of these organisms, humus is formed.
The last fourth stage of maturation begins at the moment when the temperature level of the compost is compared with a given environmental indicator.

Adding an activator - BIOTEL-compost.

Due to the composition of natural microorganisms, the process of compost maturation is effectively accelerated. Processes grass, leaves, food waste into a unique organic fertilizer. The composition is safe for humans, animals and the environment.

Mode of application:

Dilute 2.5 g of the drug (1/2 teaspoon) in 10 liters of water in a watering can and stir until the powder is completely dissolved.

10 liters of the resulting solution are calculated for 50 liters of waste.

Pour the solution over fresh waste and mix thoroughly with a fork.
Turn and mix the compost periodically for better air access.
When the compost heap or bin is full, allow the contents to mature for 6-8 weeks for fertilizer.

As winter approaches, re-treat the contents of an unfilled compost heap or bin, mix, and let mature until spring. 1 pack is for 3000 l. (3 m³) processed waste. Opened packaging should be stored closed in a cool dry place for no more than 6 months.

Compound: bacterial-enzymatic composition, baking powder, moisture absorber, sugar.

Precautionary measures: The product contains exclusively natural bacterial cultures. Wash your hands after use. Do not store the product near drinking water or food.

Compost application

The use of mature compost, if all processes have been done correctly, is already possible after 6-8 weeks. The substance should be crumbly, slightly wet and dark brown in color. If the mixture smells like earth, then the compost is ready. It is possible to prepare and apply fertilizer throughout the year for almost all crops. It is used when planting trees, shrubs and perennials. A little compost does not fit when planting vegetables in the hole.

Compost can be used as fertilizer, biofuel and mulch. As a fertilizer, compost mass is suitable for any plant crops. That is, creating a protective layer for the soil under trees or plants from drying out, weathering, washing out and enriching it with organic substances, which positively affects the development of the root system. In this case, you need to take into account the fact that not completely decomposed compost may contain weed seeds. Therefore, only well-ripened mass should be used.

As a rule, it is embedded in the soil in the autumn and winter, but it is allowed to be introduced into the soil at any other time. The rate of this fertilizer is 5 kg / m 2. The mass is covered with a rake during cultivation.

Compost should not be used as seedling soil, as it contains a high concentration of nutrients. For this purpose, the mass is mixed with sand or earth. Also, this fertilizer is a good biological fuel for greenhouses in which seedlings are grown and plants are maintained.

A thin layer on the surface of the lawn will be an excellent stimulant for the growth of juicy and dense grass, and making compost with your own hands is not difficult at all.

is a simple and low cost way to convert organic materials into a mixture to improve soil quality. When you have your own plot and enough space for a compost yard, why not take advantage of this opportunity?

This article talks about the benefits of composting, how composting works, what can and cannot be composted from waste, how to compost, how to use ready-made compost, what problems can arise in the composting process and how they can be solved. The reader may also be interested in information on how a composting dry closet works, which can be found.

Composting speeds up the natural decomposition processes and returns organic materials to the soil. Composting converts organic waste such as wood chips, sawdust, leaf litter, and many types of kitchen waste into a dark brown, crumbly mixture that can be used to improve soil quality and reduce the need for fertilizer and water. Why throw something away when you can use it for your garden?

There are two types of composting - anaerobic (decomposition occurs in the absence of oxygen) and aerobic (decomposition occurs in the presence of oxygen). In this article, I am looking at aerobic composting, in which the breakdown of organic components is due to aerobic microorganisms. With this composting, a stable end product is obtained without unpleasant odors, with a low risk of plant intoxication.

Compost is a conditioner. With it, you can get soil with improved structure and quality. Compost increases the concentration of nutrients in the soil and helps retain moisture.

Recycling food and garden waste. Composting helps to recycle up to 30% of household waste. Every day the world is thrown away, and composting can help reduce the amount of waste sent to landfills.

Introduces beneficial microorganisms into the soil. Compost helps aerate the soil, and the microorganisms contained in the compost inhibit the growth of pathogenic bacteria, protecting plants from various diseases and healing the soil.

Good for the environment. The use of compost is an alternative to chemical fertilizers.

Composting process. simple biology

No complicated equipment or expensive artificial additives are required to convert organic waste into compost. Waste composting is a natural process that occurs due to organisms found in organic materials and the earth, which, by feeding together or absorbing each other, carry out the processing of waste.

Bacteria perform the primary destruction of organic matter. Bacteria are usually not added to the compost - they are already found in almost all forms of organic matter, and they multiply rapidly under the right conditions.

Non-bacterial compost-forming organisms are fungi, worms and various insects. For them, the compost heap is a wonderful "canteen". Mushrooms convert organic compounds by introducing carbon dioxide into the soil. Worms absorb organic waste, fungi, protozoan nematodes and microbes. Worms process organic matter very quickly, converting it into substances that are easily absorbed by plants. Composting waste using worms is called vermicomposting. The combination of conventional aerobic composting with vermicomposting gives very good results. Insects, while devouring other organisms and each other, also participate in the process of processing materials in the compost.

What kind of waste can be composted?

flickr.com/ szczel/ CC BY 2.0

Composting materials can be roughly divided into brown and green. Brown (carbonaceous) materials enrich the compost with air and carbon, while green (nitrogen) materials enrich the compost with nitrogen and water. To create compost, alternate layers of brown and green materials.

Table 1 - Materials for composting

Material	Carbon/Nitrogen	Note
Food waste
Fruit and vegetable waste		Add with dry carbon materials
cut grass		Add a thin layer so that it does not lie in lumps
		Use weeds without seeds
Green comfrey leaves
Flowers, cuttings		Chop long and thick stems
Seaweed		Make a thin layer; it is a good source of minerals
chicken manure		Excellent "activator" of compost
animal dung		Enriched with microflora and easily decomposing nitrogenous and nitrogenous organic compounds
Coffee grounds		Good for fruit trees; attracts earthworms
		Available in sachets
garden plants		Use only healthy plants
Eggshell	Neutral	Better crushed
	carbonaceous	Crushed leaves are better processed
Cut branches of shrubs	carbonaceous	Wood trimmings are recycled slowly
hay and straw	carbonaceous	Straw is better, hay (with seeds) is somewhat worse
	carbonaceous	acidifies the soil; use in moderation
wood ash	carbonaceous	Use ashes obtained from pure wood, sprinkle with a thin layer
	carbonaceous
shredded paper	carbonaceous	Avoid glossy paper and colored ink
	carbonaceous	Grind material to prevent caking
Corn cobs, stalks	carbonaceous	Slowly processed, best used in crushed form
shredded tissue	carbonaceous	Made from natural fibers
	carbonaceous
Chips/granules	carbonaceous

You can also add garden soil to the compost. A layer of soil will help mask any odors, and the microorganisms found in the soil will speed up the composting process.

These components should not be added to the compost!

Although many materials can be composted, there are some materials that should not be added to compost.

Table 2 - Materials that should not be added to compost

Getting compost

Choosing a composting system

Waste can be composted in a compost heap, pit, box or trench. A bin is more comfortable to compost than a pit, and looks more aesthetically pleasing than a pile while retaining heat and moisture. You can make your own crate from scrap lumber, wooden pallets, snow fences, wire mesh, old cisterns, or concrete blocks. For example, this article gives a drawing of a compost bin and explains how it is made. You can also purchase a ready-made composting box. For starters, it's best to use a one-box system.

Place for composting waste

General criteria:

The place should be at least partly shaded;
It is better that it is at least 50 cm away from the buildings;
The place must be freely accessible so that materials can be added to the compost;
It is good if there is a source of water nearby;
Good drainage must be ensured so that water does not linger in the pile (this can slow down the decomposition process).

Adding materials

In the beginning, to create a good mixture, you can measure out equal proportions of green and brown materials. For example, an equal amount of brown autumn leaves and freshly cut grass can give the optimal combination. But if it is not possible to immediately create the optimal combination of materials, then you should not worry about it. In the course of composting, you can adjust the mixture by adding the necessary materials.

base layer. Start with brown materials. Place a 10-15 cm layer of large brown materials (such as branches) on the bottom of the pile for ventilation.

Alternating green and brown materials. The thickness of the layers of nitrogen (green) materials and carbon (brown) materials should be 10-15 cm. The composting will become more active after mixing them.

Size matters. Most materials will decompose faster if broken or cut into small pieces.

Humidification of the compost. The compost heap should look like a wrung out sponge. Squeeze a handful of compost; if water droplets appear between the fingers, then there is enough water in it. Rainwater enters the pile, as well as moisture from the greenery (freshly cut grass contains almost 80% moisture). If the pile becomes too wet to dry out, it can be agitated more frequently and/or drier brown materials added to it.

Compost mixing

flickr.com/ M. Dolly/ CC BY 2.0

After the compost pile is collected, compost-forming organisms - bacteria, fungi and insects - begin to work. In this case, you can notice that the temperature of the compost rises, steam can come from it.

For existence and reproduction in compost, living organisms that process organic matter need water and air. Water allows microorganisms to develop and move throughout the compost. Stirring the compost with a shovel or fork will allow air to enter. Approximately a week after falling asleep materials, the compost can be mixed. When mixing, it is necessary to break up lumps and moisten the pile as needed.

It is necessary to mix and moisten the compost heap until the compost is ready. The composting process can be quite fast during the summer months. The compost may stop heating after a few weeks. If the compost in the pile is dark and crumbly, has a fresh earthy smell, and no longer resembles the original materials, then it is probably ready.

Using prepared compost

flickr.com/ Diana House/ CC BY 2.0

Compost is not a fertilizer, but it contains nutrients that help plants grow. The use of compost reduces the need for watering and the use of artificial fertilizers.

Adding compost to the soil.In sandy soils, compost acts like a sponge, retaining water and nutrients for plant roots. In clay soils, compost makes the soil more porous by creating tiny holes and passages that improve soil moisture permeability.

For leveling the surface and improving the landscape.

Can be used as foliar plant food or mulch. Mulch covers the soil around plants, protecting it from erosion, drying out, and the sun.

Can be added to potting mix for indoor plants.

Composting problems and their solution

Home composting is not a very complicated process, but usually some problems are encountered in the process of obtaining compost.

Pile not heating up

Size matters. The compost pile should be at least 2 meters wide and 1.2-1.5 meters high, with such dimensions the pile retains heat and moisture.

Moisture. Do a compression test: take a handful of material and compress it. If at the same time there are no droplets of moisture between the fingers, then the pile is too dry. Stir the pile and add water.

Nitrogen. If the pile is new, it may be missing green materials. Try adding grass clippings or fruit and vegetable scraps. As a last resort, use some nitrogen-rich fertilizer.

Airing. The compost heap needs to "breathe". Use rough materials such as wood chips to create air spaces in the pile and add carbon to the mixture.
Maybe the compost is ready. If the compost has been mixed several times and has been standing for a long time, then it is probably ready. Sift the compost through a sieve and use.

There was a smell

The smell of a rotten egg. There is not enough air in the pile because it is too wet. Stir the pile with a shovel or fork to let air in. To increase airflow, you can add wood chips or some other filler.

Smell of ammonia. This indicates too much green material. Add more carbonaceous materials such as dry leaves or straw. Stir the pile thoroughly and test for moisture content.

The heap attracts scavengers and insect pests

Low fat diet. Do not add food scraps with oils, meats, or dairy products; their scents can attract animals such as raccoons or mice.

Close the compost. Cover new food scraps with carbonaceous materials and place them in the middle of the pile. The closed box will not let the big pests in. Insects are an element of the composting system, and during the process of creating compost, enough heat is created inside to destroy their eggs and reduce the number of unnecessary insects.

flickr.com/ Diana House/ CC BY 2.0

Compost preparation. Anaerobic and aerobic types of decomposition. The ratio of carbon and nitrogen. How to properly lay a compost heap.

Compost is a fertilizer obtained as a result of the microbial decomposition of organic matter.

Compost is used by almost all gardeners, regardless of what agricultural practices they adhere to, whether they dig the soil, or just loosen it, use mineral fertilizers, or do without them.

In almost any garden, and kitchen garden, there is a pile, or pit, for recycling waste from the kitchen and garden debris. Someone for composting builds all kinds of boxes, barriers, using metal mesh, boards, slate - any material that encloses a place adapted for composting organic waste.

The resulting compost has a loose, breathable structure and is enriched with all the nutrients needed by plants. In fact, compost in the garden is very good!

And almost every gardener considers himself an expert in this matter, but some simply do not think that compost can be prepared in various ways: “What's so difficult? He threw in a bunch of weeds, herbs, dumped kitchen waste in the same place, watered it, and wait until it all rots!”

In general, right. But I would like to understand a little more about the biological processes that occur during the decomposition of organic matter, so that composting in the garden does not take place spontaneously, but according to a planned scenario.

Anaerobic

It is also called "cold", proceeds at temperatures of 15 - 35 ° C, with the participation of anaerobic microorganisms that receive energy in the absence of oxygen.

The compost heap with such composting is rammed, covered with a film, or laid in pits. But, it is better to refuse such a composting method. Why?

A significant disadvantage of this method is the slow decomposition of organic matter, and the process of decay itself, with a lack of oxygen, can become harmful to plants, provoking the development of fungi, including pathogenic ones.

In anaerobic fermentation, the carbon present in the fermenting materials is not converted into carbon dioxide, as in aerobic fermentation, but into methane. Hence the bad smell. In nature, this process occurs at the bottom of swamps, and in compost heaps it can occur at high compost moisture.

Aerobic

Faster, proceeds at higher temperatures, without an unpleasant smell. Most gardeners prefer aerobic composting, that is, with air access.

Although it must be admitted that in the compost heap, both aerobic and anaerobic processes occur simultaneously. If there is more oxygen (air) in the upper layers of the compost heap, then, accordingly, aerobic composting will prevail there.

Aerobic fermentation occurs in nature on a large scale and is the dominant way in which waste from fields and forests is converted into humus that is beneficial to soils and their inhabitants.
Therefore, gardeners most often strive to use this particular method, systematically mixing (shifting) decaying organic matter in a pile to provide it with air.

It happens that the compost mass sometimes heats up to 70 ° C, as it were, “burns out”. Rejoice at such temperatures, or not?

There is an opinion that hot composting leads to the destruction of pathogenic organisms, as well as to the fact that weed seeds that fall into the compost heap lose their germination.

As experiments have shown, seeds that have undergone heat treatment in a compost heap still partially germinate, so when laying grass for composting, you should avoid collecting weeds after they bloom.

Learn more about the composting process

At the first stage, all microbes present take part in the processing of waste. At the same time, there is an intensive process of oxidation, that is, interaction with oxygen, during which heat is released.
The most striking and fastest example of oxidation as a chemical process is combustion. As for the decomposition of organics, this oxidation is slow, and heat (energy) is released slowly during this process.

But what happens to microorganisms at this time? They will die from the high temperature.? The fact is that there are a number of so-called thermophilic bacteria that develop at high temperatures (above 50, up to 90 ° C, depending on the species).

The cell membrane of thermophiles is temperature resistant. This is due to its structure and chemical composition. It is these bacteria that continue their work, it is they who heat the compost heap to a critical temperature at which other microorganisms cease their activity.

Some microorganisms die, and some pass into an inactive form (cysts) in order to survive as a species. Cyst (from the Greek kystis - bubble), a temporary form of existence of many unicellular plants and animals. It has a protective sheath, also called a cyst.

Some protozoa can exist in unfavorable conditions in the form of a cyst for several years.
Later, the activity of thermophiles will decrease, as will the temperature in the compost heap itself. Bacteria dormant in cysts will come to life and continue their work. With favorable temperature and humidity indicators, new microorganisms will colonize the compost and continue the process of decomposition of the compost heap components.
From the above, it follows that high temperatures, indeed, can partially destroy certain types of microorganisms - both harmful and beneficial.

But, pathogenic microbes tolerate adverse conditions better, so the assertion that hot composting disinfects compost is not entirely legitimate.
Many experienced gardeners keep their compost heaps small and low so they don't heat up as much. Such heaps are quickly populated by worms, which in turn leads to more valuable and nutritious compost.
When laying organic matter for composting, it is worth considering one more circumstance.

Organics is nothing more than a combination of various chemical elements with carbon.

In addition to carbon, nitrogen plays an important role in nature - an important building material for amino acids, proteins, nucleic acids and other compounds.
And the organic materials that we use for composting contain both carbon and nitrogen and are characterized by the ratio of these chemical elements.
So, for example, in sawdust, the approximate ratio of carbon to nitrogen: C / N \u003d 500/1
in straw С/N =100/1
in foliage С/N =50/1;
in lawn grass С/N =15/1
in vegetable waste С/N =13/1
manure compost С/N=10/1
This means that the compost obtained as a result of the decomposition of grass will be more saturated with nitrogen than the compost obtained with a predominance of sawdust.

Therefore, when laying a compost heap, one should alternate or mix nitrogenous components with carbonaceous components.

That is, it’s good to mix sawdust with manure, and shift vegetable waste with dry foliage, etc. Tree branches should definitely be chopped, grass should be chopped, if possible.

The smaller the components, the faster the decomposition process will proceed.

What is usually put in the compost heap?

Waste from the kitchen: vegetable peelings, egg shells, offal and fish bones. And also, shavings, sawdust, paper, weeds, grass cut from lawns, leaves collected from under trees, straw, brushwood.

It is advisable to sprinkle the layers of components with wood ash, then the compost will be more nutritious.
Through a layer of 25-35 centimeters add a little earth "for sourdough".
It is desirable to shed each layer with an EM preparation, this will significantly speed up the composting process. After 5 - 10 days, the pile, if possible, is mixed, and when it dries, it is moistened.
If EM preparations are not available to the gardener, to speed up composting, you need to lay some ready-made compost saturated with microorganisms. If there is no such possibility, you should use sourdough, from grass, manure, land from the garden. Well, you can not add anything, using the rule “And so it will do!”, But then the mature compost will be obtained at a later date.

Composting allows you to get valuable organic fertilizer and dispose of waste that becomes harmless to the environment.

“Fast composting. Compost in one season is made by larvae "-

03 09.18

How to increase the rate of maturation of compost at home?

Homemade compost is a versatile organic fertilizer that can be used on any plant or crop. For its preparation, various wastes are used: cut grass, rotten fruits and vegetables, manure, shells, etc.

What is compost for?

Such organic fertilizer is used not only for the growth of plants and crops, but also to increase soil fertility. This process is carried out in autumn or spring. A thick layer of fertilizer helps to retain the moisture necessary for plant growth, strengthens the root system, saturates the soil with nutrients, and also prevents the growth of weeds.

Thanks to this product, you can not only increase soil fertility, but also get rid of unnecessary plant residues located in the garden.

Many landowners combine organic fertilizers with nitrogen-phosphorus-potassium components to achieve better results. For example, in the fall, along with compost, potassium sulfate or other phosphates are added to the soil.

Despite the versatility of compost, it is not enough to ensure sufficient growth of fruit and vegetable crops. "Black gold", as gardeners call it differently, can be made from 6 to 12 months. Consider simple ways to accelerate the growth of compost.

Ways to accelerate the maturation of garden compost

Maintaining the required humidity. During the manufacturing process, organic fertilizer must be watered at least once a week. This feature will speed up ripening by about 2 months. Many experts recommend watering with a solution of litter or manure. This will speed up the process even more.

Humidity fluctuations have a huge effect. If the fertilizer dries up, then useful trace elements die, and it takes time to restore them. The top layer of compost should be earthy. Another option is to cover the fertilizer with a film and make holes in it for oxygen to enter. All these activities will certainly accelerate maturation.