What is compost and how is it made


Compost is some kind of organic fertilizer, which contains rich nutrients, and has a long and stable fertilizer effect. In the meantime, it promotes the formation of soil solid grain structure, and increases the soil’s ability to retain water, heat, air, and fertilizer.Also, compost can be mixed with chemical fertilizers to supply the shortcomings of the single nutrient contained in chemical fertilizers, which would harden the soil and reduce the performance of water and fertilizer retention with long-term use. Therefore, historically, compost have always been valued by the planting industry.

1.How to make compost?

Generally speaking,compost is made of various animal and plant residues (such as crop straw, weeds, leaves, peat, garbage and other wastes, etc.) as the main raw material fermented and decomposed under the conditions of high temperature and humidity.Because its composting materials and principles,and its composition and properties of fertilizer ingredients are similar to manure,so it is also called as artificial farmyard manure.


Compost has very long history, and its basic production method consists of the following steps:

1.Collecting raw materials: collect local planting waste (such as straw, vines, weeds, fallen leaves of trees), production or domestic garbage (such as pond mud, sorting garbage, etc.), and excrement from aquaculture ( For example, livestock manure, washing wastewater, etc.) are gathered and used as raw materials for composting;

2. Raw material processing: properly crush plant stalks, stems, branches, etc., and crush them into a length of 3 to 5 inches.

3. Mixing of raw materials: All raw materials are properly mixed, and some people will add an appropriate amount of calcium cyanamide to promote its fermentation.

4. Composting and fermentation: Covered by broken mats, rags, straw or plastic cloth to avoid loss of fertilizer,and placed in a composting shed would be the best. If there is no composting shed, open-air composting can also be optional, but an appropriate location must be selected to avoid loss of fertilizer due to the sun, rain and wind.

5. Turning compost into maturity: In order to ensure that the compost is evenly fermented and decomposed inside and outside, the compost must be turned over for every 3~4 weeks. After about 3 months, you can start using it.



2.How to make compost more efficiently?


Composting can be divided into two methods: normal composting and high-temperature composting. The former came with fermentation temperature, and the latter has a higher pre-fermentation temperature.


Normal composting is actually the composting method adopted by the planting industry for thousands years.We call it the “traditional composting method”. By this method, which adopts simple mixing, artificial stacking, and natural fermentation, can also be called “waterlogged composting”. The whole process would take very long time,with heavy odor during the fermentation, and serious nutrient loss. So this is not the modern composting method we comply now.


The compost heap on this picture is more random ,which is close to the farm or the orchard with a little open space,by pulling over the manure, straw, etc. and centralized stacking in one place. In some other place, it need to be stacked for several months before using.


For the high-temperature composting, ferment is generally required.The high-temperature fermentation of the mixed raw materials promotes the rapid fermentation and maturity of the fermentation substrate, and at the same time, it can kill the inside germs, insect eggs and weed seeds .This is the right way to make compost now, and it is also the part described in detail of this article.

As the selection of facilities,there are two methods for high-temperature composting: semi-pit stacking method and ground stacking method.

The semi-pit stacking method has now been transformed into a fermentation tank after factory production, which is conducive to mechanized operation and improves efficiency.


The ground stacking method also requires the cooperation of various compost equipment to improve production efficiency.

You can find out that modern organic composting is already different from the traditional method:


Traditional compost High temperature composting
Raw material Manure, straw, garbage, peat Manure, straw, garbage, peat
Fermentation agent Generally not added Add special fermentation inoculants
Lighting conditions Direct natural light, direct sunlight Generally have awnings
Natural influence Wind and rain, high temperature and low temperature Only low temperature affects
Nitrogen, Phosphorus and Potassium Maintenance Serious loss Fully maintained
Organic matter preservation Mostly maintain Fully maintained
Humus retention Partially formed Mostly formed


The following comparison table express the differences more intuitively:

The above is a simple comparison of the characteristics of the “organic compost” produced by the two methods, but not comprehensive. But we can still see the difference. Of course, it’s up to you to judge which way is better.

We can also find from the table that the raw materials used in fermentation are basically the same.

The point is that in the production process, the high-temperature accumulation method has made many improvements.There can be many combinations of organic raw materials for composting: for example, livestock manure, gasket materials, and feed residues are mixed and stacked; crop stalks, green manure, weeds and other plant materials are mixed with soil, human feces, garbage, etc…. …

Stacking requirements: Mix all kinds of raw materials as evenly as possible; the general compost windrow height is 80-100 cm; the moisture content is not less than 35% and not more than 60%; maintain good air permeability.

Basic principle: Use aerobic bacteria for efficient fermentation, quickly decompose a variety of organic matter, form small molecular nutrients and humus, and produce a variety of microbial metabolites at the same time, which is conducive to plant nutrient absorption, root protection and soil improvement.

Process summary: screening (crushing)-mixing-fermentation (turning the pile)-maturity-(modulation)-finished product. Compared with other production processes, this process is much simpler. The core technical point is “fermentation (turning the pile)”.

Compost fermentation is closely related to fermentation bacteria, temperature, humidity, time, type, size, and turning time of fermentation substrates.

We have found some problems or misunderstandings in the actual operation of many fermentation sites, and we will select a few key points to share with you:

  • Fermentation agent: Not as long as the fermentation could product high temperature is the “good fermentation agent”. Effective fermentation agent only use very simple bacteria seed, and actually only 1 or 2 kinds of fermentation bacteria are working. Although it can produce high temperature effects, it has low efficiency in the decomposition and maturity of other substances, and the composting effect is not ideal. Therefore, the right fermentation agent is the best choice!
  • Raw materials sieving: Due to the miscellaneous sources of fermentation raw materials, they may contain stones, metals, glass, plastics and other sundries. Therefore, the sieving process must be passed before compost production. the sieving process must be necessary to ensure avoid personal injury and equipment damage, and the high quality of product. In the production operation, many production plants “think it is trouble”, and cut off this process, then finally causing lost.
  • Humidity requirements: not lower than 40%, nor higher than 60%.Because the humidity is higher than 60%, it is not conducive to the survival and reproduction of aerobic bacteria. Many producers do not pay much attention to water control, which leads to fermentation failure.
  • Fermentation turning compost: Many producers do not do windrow turning when the fermentation stack reaches 50-60 ℃ during the fermentation process. Moreover, many “technicians” guide their customers by saying that “generally, fermentation should be above 56 ℃ for 5-6 days, and high temperature of 50-60 ℃ for 10 days will be enough.”