How are nutrients replenished in the soil?

The plants absorb all the essential nutrients like potash, phosphates, nitrates and other nutrients from the soil. These nutrients will be deposited in the plants. After plants are cut down or due to maturity has fallen down on the surface of the soil. The plants get decomposed and the same nutrients get back to the soil – a Natural process of nutrients replenished in the soil.

During winter most of the leaves are fallen down. When all this fallen down plants combine with soil and the moisture starts to decompose. The decomposition is instigated by the microorganisms like bacteria, fungi. The decomposition of these fallen plants releases nutrients back into the soil. All these nutrients are stored in the plant body and also leguminous plant roots get released to the soil. All the nutrients taken by those fallen plants will be given back to the soil for the new plants to consume. This is one of the normal nutrient cycles which Nature follows.

Some of the ways nutrients are replenished in the soil are

1. Crop rotation
2. Natural Mulching
3. Cover crops
4. Composting

1. Crop Rotation

As a human, we come up with innovative ways to increase the nutrients in the soil. Remember we can only enhance by mimicking Nature. How can we replenish the soil with more nutrients? The answer is crop rotation. Crop rotation from outside looks like farmer changes crops based on the market prices of the crop. Which is partially true. But let’s dig in the true secret behind crop rotation.

The scientific reason behind Crop rotation is to replenish nutrients in the soil. The process of changing crops season after season on the same piece of land is called crop rotation. This practice goes behind a few thousand years. Farmers gathered thousands of years of knowledge to know growing the same crop again and again in the same land will decrease the yield over the period of time.

If the crop rotation is not carried out 

1. Land becomes less fertile and tired. The same type of plants keeps on draining the land of the same nutrients needed for their growth.
2. The pests control will become very difficult as they stay for a very long time on the same crop and they multiply a lot. As most of the pests reach resistance level where it will be hard to control.
3. The land is more exposed to more soil erosion if the same type of crops is repeated season after season.

The nutrients are replenished in the soil by crop rotation. Changing the crops for every season will keep the land fertile. When one type of crop drains the nutrients in one season, then in the nest season plant different type of plant which will give back these nutrients to the soil. As we know most of the legumes replenish nitrogen in the soil. Rotation of crops helps to improve the stability of the soil. Some will have deep roots and some with shallow keeps the soil intact in all the seasons. Crop rotation increases yields and prevents crop loss due to pests.

Usually, Crop rotation periods depends on what crops are sown, sometimes every 3 months, a few times 6 months or 9 months. It all depends on the location, rainfall, market prices. So never plant the same crop again in the next season in a row.

2. Natural Mulching (Cover Crops or Green Mulch)

Mulching is the way of covering the soil surface with any material to suppress weeds, conserve water and enhance decomposition. I prefer Natural mulching – either growing a green cover crop(Green mulch) or adding a dry straw. My farm initially I covered with dry straw and some Neem (Azadirachta indica) leaves, which helped to suppress weeds.

As my farm has very less water, I waited for rains to add green mulching. After the rains, I added alfalfa (horse gram) and Changeri(Oxalis corniculata) which grow tremendously fast. The technique is also called as Cover crops or green mulch. The roots of Changeri are shallow, this has a lot of medicinal values used extensively in Ayurvedic medicines. You can always leave Changeri to grow all over your farm, this will be natural fodder for your farm animals as well.

Legumes like alfalfa, green peas are also added after the rainy season. These act both cover crop and also nitrogen fixation. The Nitrogen balance is maintained by these legumes.

Mustard according to Offthgridnews.com contains high levels of glucosinolate. These act as a natural toxic to pests that will kill nematodes in the soil. A lot of organic material also added to the soil due to its vigorous growth. The break down of organic material replenishes nutrients in the soil.

1. Mulching improves the nutrients and water retention in the soil.
2. Encourages microbial and earthworms activity by creating a microclimate.
3. Weed growth is suppressed
4. Soil erosion is kept under control and also reduces evaporation.
5. Decomposition of these Natural mulch is an added advantage to replenish nutrients in the soil.

Cover crops can be treated as the plants which will grow right next to the main crops. Cover crops do not compete for nutrients and water with the main crops. In fact, it will add more nutrients to the main crop. As Cover crops outgrow and compete for only weeds, we should always keep cover crops around. Once they are matured(When flowing starts) cut down the cover crop ( use hand till) allow it to form a dry mulch. These will again decompose to add nutrients to the soil. Any plant which takes nutrients while its growing will give back the same nutrients back to the soil after it gets decomposed.

3. Composting

Composting is the process of decomposing the organic matter. The way composting is carried out by humans and the other way is by nature. Humans collect the cow dung, dead leaves, kitchen waste and also green leaves. Now add water to keep it moist. Later in-order to aerate once in few days you got to mix them. Then leave for a few days to break down to form compost. The other way is Nature takes care of composting naturally, if you mulch. For big lands “Mulching composting” is a better approach. Which reduces labor work, time and no cost involved. For small land farmers, they can do mulching.

Compost contains a lot of nutrients which is also called humus. Humus will replenish nutrients in the soil. The Natural way of composting balances nutrient deficiency.

Main nutrients required for plants are

• Nitrogen – major component of chlorophyll, the compound by which plants use sunlight energy to produce sugars from water and carbon dioxide (i.e., photosynthesis).
• Calcium – Required for plant growth and structure.
• Manganese – Required mainly for photosynthesis.
• Carbon – Required for plant growth

Crop rotation, Composting, Cover crops and Mulching all these techniques replenishes nutrients in the soil. Along with that, it will help to control pests, prevent soil erosion and allowing main crops to produce more. Using the above techniques will reduce a lot of burden on the farmer, he can keep his farm free from chemical pesticides and fertilizers. So that he can completely avoid farm loans. Free from debts. The first step towards Chemical-free farming and also disease-free farming.