You will love this in-depth guide if you want to learn about the importance of composting in agriculture.
But first, you might be wondering, what is compost?
In simple words, this organic matter made from decomposed plants is used for gardening and agriculture.
I will explain this to you in detail.
But first, the NPK of compost is commonly 2-1-2. But first, let me tell you what this shows.
What Does NPK 2-1-2 Mean?
This value shows the percentage of three elements in compost:
- Nitrogen (N): 2%
- Phosphorus (P): 0.5 – 1%
- Potassium (K): 2%
Here’s how these macronutrients are essential for your plant.
This nutrient is extremely important for plant growth.
It is a source of energy for metabolic reactions in plants.
Respiration, photosynthesis and nitrogen fixation are some examples of metabolic reactions.
Moreover, it results in good leaf growth in plants. Can you guess why is this so?
Nitrogen is used to make nucleic acid, DNA (Deoxyribonucleic acid) and proteins. As you already know, amino acids have multiple roles in plants.
- They act as signal molecules.
- They regulate flowering time.
- They regulate shoot and root architecture.
Amazing, isn’t it?
For your reference, let me tell you that plants take up nitrogen in form of NH₄⁺ and NO₃⁻ ions. It may also obtain nitrogen in form of nitrates.
Now let’s talk about Phosphorous.
It is a component of ATP (Adenosine triphosphate). Here’s what this means.
ATP is a structure that provides energy to plants.
In the same way, Phosphorus is required for growth and metabolism in plants. It also supports the shoot and root system of plants.
It results in fruit and flower development as well. Can you guess how a plant obtains this nutrient?
A plant takes up phosphorus in its primary forms. We call them orthophosphates, H2PO4– and HPO42-.
Now, let me introduce potassium to you.
Recall that compost commonly contains around 2% Potassium.
Plants use this nutrient for the movement of carbohydrates, water, and nutrients. It also activates enzymes that make proteins, starch and ATP.
Note: Enzymes are biological catalysts. They speed up a reaction.
Remember that it also regulates the opening and closing of stomata (involved in gaseous exchange).
It is taken up by the plant in form of potassium ion (K+). Now, let’s talk about compost.
What is Compost?
It is decayed organic matter. Let me explain.
Let’s say you have dead leaves, leftover food, lawn trimmings or dead plant matter. Aerobic and biological bacteria turn it into compost.
The best part is that we use compost to fertilize our soil. I will explain this later in this article.
But to overview, here’s why compost is important in agriculture.
- It improves soil fertility in organic farming, urban agriculture and gardens.
As a result, our dependency on chemical fertilizers reduces.
- It provides nutrients to crops.
As I mentioned above, the three important macronutrients, Nitrogen, Phosphorus and Potassium, are found in well-rotted compost.
- It regulates soil pH.
The majority of finished composts have a neutral pH (from 6 – 8). As a result, well-decomposed compost can reduce the pH of your soil.
I will take about all these points in detail. But first, let me tell you how composting is done.
How is Compost Prepared?
At a very basic level, we gather green waste and brown waste.
Green waste refers to materials that are rich in nitrogen. For example leaves, food scraps and grass.
Can you guess what us brown waste?
Brown waste refers to woody materials that are rich in carbon. Wood chips, papers and stalks are some examples.
Then, these materials are broken down into humus (an organic component of soil). This is done when water is added as bacteria use water and oxygen to break the material down.
Pretty simple, isn’t it?
For Home Gardens:
As I mentioned above, this is done on a small scale.
We gather yard waste and kitchen scraps. For proper decomposition, aeration (circulation of air) is essential.
To understand more about this, here are three methods to make compost.
Types of Composting:
In this process, organic matter is converted into compost in the presence of air.
Note that the microorganisms present in compost are naturally occurring. Plus, they usually live in the moisture that surrounds organic matter.
So when oxygen is taken up by the microbes, digestion starts.
As a result, heat, water, carbon dioxide and ammonia are given out as by-products.
Note that the heat produced in this process kills pathogens and bacteria that are not adapted to a heated environment.
There are many methods of aerobic composting. But here’s the most simple one:
- Organic matter is divided into three layers that are placed over one another.
- This layer of organic matter is then covered by dry leaves or a thin layer of soil.
- This pile is then mixed every week. After three weeks, the conversion takes place.
Pretty simple, isn’t it?
This type of composting occurs with little to no oxygen.
So, the decomposition is done by microbes which DO NOT require oxygen to survive.
Note that in this process, less heat is released. Plus, most of the energy is converted into methane.
This heat is not enough to kill bacteria and pathogens. But sometimes, artificial heat is added to overcome these limitations.
Can you guess what happens next?
When the material is broken down, it is converted into a sludge-like material. This material is tougher to break.
To recap, organic material is collected in pits. This is then covered with a thick layer of soil which is left for 6-8 months.
Microbes that do not require oxygen then decompose it. Now, let me introduce vermicomposting to you.
The name sounds difficult, but the concept is simple.
Let me explain.
In this process, worms are used to convert organic matter into compost. But how?
The earthworm eats organic matter. It gives out the digested matter in the form of vermicompost.
Note that earthworms weigh about 0.5 grams. And they eat matter equal to their weight. Some other things that can be converted into vermicompost are :
In the same way, livestock wastes, poultry litter and dairy wastes are also part of vermicomposting.
Importance of Composting in Agriculture:
Compost is one of the best organic fertilizers.
Why is this so? Let me explain.
- It is rich in carbon.
Now you might be wondering, why is carbon important for plants?
It is important in building plant tissues. This is because it is needed for energy.
Note that the microbial oxidation of carbon produces heat. This heat is then used for the composting process.
Recall that carbon dioxide is used by plants to make food through photosynthesis.
- It also contains Nitrogen, Phosphorus and Potassium.
We have already discussed the importance of these nutrients. But here’s a thing.
The amount of these nutrients in compost is low. Therefore, we add compost in greater quantity to fulfil the nutrient requirements.
- It reduces dependency on chemical fertilizers.
We know that compost improves soil structure by providing essential nutrients.
This reduces the need for chemical fertilizers to fulfil the nutrient requirement. But why is this important?
Remember that chemical fertilizers are made up of harmful chemicals. These chemicals cause water and soil pollution.
In the same way, compost is inexpensive. In case of a global pandemic, it is a great alternative to chemical fertilizers.
Amazing, isn’t it?
- Compost allows the soil to retain more moisture by aerating it.
This simply means that it improves the water holding capacity of the soil. This is because it reduces soil crusting.
Soil crusting: It is a thin layer of tough and dense material.
This thin layer has high penetration resistance and high bulk density. But compost reduces this.
So this is the reason why compost makes water absorption and penetration easier.
Note: Microbes (such as bacteria) cannot survive without proper moisture in the soil.
This is the reason why compost improves soil tilth.
- Compost lowers greenhouse gas emissions.
Talking about the importance of composting in agriculture, here’s what you need to know.
Greenhouse gases trap heat in the atmosphere. As a result, the temperature increases. These gases include:
- Carbon dioxide
- Nitrous Oxide
Compost reduces methane emission through aerobic decomposition. This is because methane-producing microbes are absent in the presence of oxygen.
It also improves carbon sequestration (a process of storing and capturing atmospheric CO2) in the soil.
In short, compost is eco-friendly.
- The application process is simpler as compared to chemical fertilizers.
When it comes to chemical fertilizers, you have to apply them over time. But, you can apply compost only once.
Usually, you should add compost to your soil in spring every year. You can also add it during the fall.
The point is that compost should be added at the start of the growing season.
- It reduces natural gas usage and the dependence on foreign petroleum resources.
Let me explain.
As I mentioned above, the composting process produces heat. This heat can be used as renewable energy.
This energy can be used in agriculture as well. Simple, isn’t it?
- The nutrients present in it improve fruit growth.
Talking about fruits, compost can maximise its growth if added in spring.
This is done by balancing soil density.
Balancing soil density:
If the soil is too tight, compost helps to loosen the soil. In the same way, loose soils are “clumped” together.
The idea is that this balancing allows the plant to develop healthier roots.
- It improves the pH of your soil.
Note that well-decomposed compost improves soil pH. As we already discussed, compost has a pH between 6 – 8.
This can make your soil slightly acidic which favours the growth of fungi. Fungi break down organic matter to create humus.
Note that some nutrients are MORE available under acidic conditions. In the same way, some are more available under alkaline conditions.
A soil pH of 6.5 is usually considered perfect for nutrient availability.
- Pathogens in soil are killed.
The heat produced during the composting process kills pathogens. This is done by introducing useful colonies of microbes.
Summary: If I talk about the importance of composting in agriculture, it is a source of nitrogen, phosphorus and potassium. Moreover, it reduces dependency on chemical fertilizers.
In the same way, it improves the pH of your soil as well.
Now, let’s talk about the disadvantages of compost as well.
Disadvantages of Compost:
- The first thing is that compost has an unpleasant smell.
But, why is that so?
There can be multiple reasons. It may be too wet, or there is a lot of green waste (rich in nitrogen).
This bad smell can also attract mice and snakes. It may also disturb the people living around.
To get rid of it, mix green and brown waste properly. Plus, try to shred material such as vegetable scraps and leaves.
- It can spread diseases.
Pathogens can interbreed in compost. In fact, these pathogens have harmed many farmers as well.
Note that Compost can be hazardous.
This can be a problem. Here’s why.
- If it is too hot, it can kill the beneficial microbes in it.
- If hot compost is packed in a tight space, it can produce a great amount of methane.
- If hot compost is enclosed in a bin, it can catch fire and even explode as well.
- It requires space and time as well.
Now, let’s jump straight to the conclusion.
So, there you have it. Our topic about the importance of composting in agriculture has come to an end.
To summarise, compost is rich in carbon. Plus, it is a source of nitrogen, phosphorus and potassium.
To recap, we covered the advantages and disadvantages of compost. Moreover, we talked about the types of compost as well.
If you have further questions, feel free to get in touch. Stay tuned for more.