You frequently hear about composting tools, composting methods, and so forth, but when it comes down to it, how does composting work?
In the following, we will start by providing you with an overview of this natural phenomenon, and then delve deeper into its complex processes. We will also mention the factors that affect it and explain why they do so.
Composting is an intricate process involving many different organisms, and that results in a new material which is nutritious for your garden. You could also say that it is a delicate process, for there are many factors which affect both the process and the final product.
Composting is a very old practice, but it seems to have become especially popular lately as more and more people have once again started growing their own food.
An Overview of the Composting Process
The answer to the question, “How does composting work?” is very complex.
- Composting is the process whereby microorganisms and macroorganisms affect organic matter. Namely, they decompose it in such a way that it becomes safe and healthy for garden use.
- Oxygen is a key component, as the bacteria that you want working in your compost pile are aerobic.
- A compost pile must consist of two types of organic matter.
- These are generally referred to as brown and green material.
- Brown material: includes things like dead leaves and produces carbon.
- Green material: consists of food, grass clippings, and other similar items and produces nitrogen.
- Both must be present if you want the decomposition process to occur properly.
- The decomposition process begins when bacteria start feeding on the compostable matter.
- Their activity raises the heat within the pile and attracts other microorganisms.
- More exactly, actinomycetes and fungi.
- At the same time, macroorganisms, such as ants, spiders, earthworms, snails, and slugs, digest and excrete the organic material.
- The microorganisms will then continue the composting process by feeding on their excretions.
How Does Composting Work?
How does composting work, then, in detail?
- The composting process starts when you collect a pile of organic matter.
- Psychrophilic bacteria are the first to attack this matter.
- These thrive in relatively cool temperatures, specifically 50 to 70 degrees Fahrenheit.
- Through their activities, they heat up the pile above their optimal range.
- In doing so, they attract the next kind of bacteria, known as mesophilic bacteria.
- As mesophilic bacteria work on the organic materials, they too cause the temperature to increase.
- When it reaches about 100 degrees Fahrenheit, they either change their field of operations to the outermost layers of the pile, or they simply do not survive.
- This is the point at which the thermophilic bacteria get involved.
- Thermophilic bacteria can survive rather higher temperatures.
- They perform optimally when the pile is somewhere between 113 and 160 degrees Fahrenheit.
- As they work on the matter, these bacteria continue raising the temperature until it stabilizes at somewhere between 130 and 160 degrees Fahrenheit.
- This state of affairs lasts anywhere in between 3 to 5 days, that is, if humans don’t get involved.
- As the pile cools, the mesophilic bacteria once again become active and even dominant.
There are two other types of microorganisms active at the same time as the bacteria are at work.
- The first are actinomycetes.
- These prefer temperatures in the moderate range.
- Actinomytes decompose all the elements that the bacteria couldn’t handle.
- Namely, they work on things such as proteins, starches, lignin, and cellulose.
- In the process, their activity produces nutrients such as carbon, nitrogen, and ammonia.
- The second type of microorganisms at work is fungi.
- These tiny organisms have to follow the bacteria and decompose the lignin and cellulose they leave behind.
- Fungi are usually most active in the last phases of composting.
- As the decomposition advances, the compost pile also receives visits from macroorganisms.
- Earthworms, for example, make it easier for the microorganisms to work on the organic matter.
Factors that Affect Composting
How does composting work in relation to its environment?
Composting is, most certainly, not a completely independent process. On the contrary, there are several different but intertwined elements which come into play during the composting process. When these are optimal, the process occurs most rapidly and can lead to the best results.
- Bacteria live and thrive in carbon and nitrogen.
- The amount and proportions of carbon and nitrogen contained in the compost pile are very important.
- The green and brown matter must balance each other out in a ratio of approximately 1 part nitrogen to 30 parts carbon if you want to achieve optimal results.
- Oxygen is necessary for the survival and operation of aerobic bacteria.
- As decomposition advances, there is less oxygen available within the compost pile.
- Although movement, especially from the macroorganisms, does allow aeration to occur naturally, human intervention is often required.
- These can help ensure that the necessary oxygen requirements are met.
- Water is yet another essential element for both bacteria and the other microorganisms.
- In fact, these can only operate when the organic molecules are dissolved in water.
- For optimal effect, you want the moisture content of the compost pile to be somewhere between 40 and 60 percent.
- If these percentages drop, then the microorganisms cannot act.
- If these levels are too high, then the water might drive out the oxygen supply.
- The best temperatures for decomposition were calculated to be in between 90 to 140 degrees Fahrenheit or 32 to 60 degrees Celsius.
- The activities of the bacteria heat up the pile, as do the external weather conditions.
- Summertime is the best time for decomposition.
- During winter, decomposition will likely slow down and possibly even stop.
- The greater the surface area available to the microorganisms, the better they operate.
- Decomposition does not occur within the organic material, but rather where the surface meets the air.
- Particles that are too large will slow down decomposition
- Particles that are too small will drive out the oxygen from within the pile.
As you start investigating the question “How does composting work?” you discover that this requires the joint activities of many different kinds of organisms.
The numerous details which go into it and affect the process make it all the more fascinating. If you have any other information to add, please feel free to share it with us in the comments below.
Perhaps now you’re interested in taking up composting yourself? Then maybe this compost bin will help get you started.