Soil fertility is a serious problem.
Once your soil starts lacking these essential potassium, zinc, nitrogen and phosphorus, your plants will have poor quality and growth.
Hence, you need to constantly build the health and vitality of the soil so that you get a good yield.
You can add nitrogen, calcium, phosphate sources naturally to your soil by composting, adding lime and much more.
This article discusses how you can retain the fertility of your soil and improve its nutrient content to get healthy growth.
Keep reading below to know how you can periodically keep improving your soil.
Checking The Fertility Status of Your Soil
When your plant crops are in your soil, they use up the nutrients in it.
Hence, after a crop rotation, to grow more crops and plants, you need to rebuild the vitality of the soil.
Nature does it too in rainforests and grasslands.
Rainforests contain a diversity of microbes, animal and plant species that help in naturally rebuilding the soil health without human intervention.
However, that process is very long and requires patience.
If you want to make the soil fertile again, you will have to incorporate other natural elements to fulfill the soil’s needs.
Though, how can you identify the soil’s needs?
Usually, soil that is dark in color and has a loamy texture is more fertile.
They also contain high soil organic matter hence, they are full of nutrients.
Sandy soils that are lighter in color, do not seem fertile.
However, to determine the type of fertilizer input and the nutrient deficiency, you need to observe and test.
Observing your plants will make you gather what the soil needs.
For instance, their growth as well as the abundance of a particular weed or grass can highlight the nutrient deficiency.
An example is the weed Striga which is dominant in infertile soils however, as soon as you apply fertilizer, it decreases.
A plant may not only wilt because of nutrient deficiencies but also due to pests and diseases.
Hence, you need to observe their stems, roots and leaves closely to identify any damage from pests and infections.
There are apparent symptoms of nutrient deficiency too.
If a plant shows these symptoms, then the soil likely lacks the nutrient too.
These nutrients are micro and macro elements.
- Macro elements like carbon, oxygen and hydrogen are present in air and water.
- Magnesium and sulfur are also macro elements present in soil solids.
- Macro elements Nitrogen, Potassium, Calcium and Phosphorus are present in soil solids and air.
- Microelements are also known as trace elements are present in soil solids, such as iron, copper, manganese, zinc, cobalt, chlorine, molybdenum and boron.
The most essential of these to the soil is Nitrogen, Potassium and Phosphorus that they require in a large quantity.
If plants lack it they will have poor growth and stunting initially.
They may also mature earlier than their time or even too late.
The products do not have a good quality, appearance and taste wise.
They also lack firmness and moisture.
Furthermore, the root growth is abnormal.
The growth of plants with nutrient-deficient soil will be different from those around it.
Moreover, the appearance of leaves will indicate how the plant isn’t receiving nutrients such as the yellowing of leaves.
Once, you know the deficiencies through a soil test, you can try different methods to raise the fertility of the soil.
Let’s find out about them below.
How To Improve Soil Fertility- Nitrogen
There are plenty of ways to increase nitrogen in your soil.
You can use manure, plant products and animal products.
Animal manure supplies nutrients according to the species, their feed, the time when manure is applied to soil and soil conditions.
It contains 10 to 15 pounds of Nitrogen, 10 to 12 pounds of potassium and 5 to 10 pounds of Phosphorus per ton.
Raw manure and composted manure can both increase the nutrient content of the soil.
Though poultry manure has a larger quantity of NPK.
To classify as compost, the material should have a carbon to nitrogen ratio between 25:1 to 40:1.
Compost can be from animal waste and plant waste.
The carbon and nitrogen content comes from carbohydrates and amino acids as nature breaks down organic matter.
Composting provides nitrogen to the soil and you can apply plant compost without any time restrictions.
Though, you need to be careful with animal compost as raw manure has certain time constraints.
You should not apply it up to 120 days before harvest.
The ratio of NPK in soybean meals is 6-1.4-4.
Hence, it is rich in essential macro elements.
Though, it is costly to use.
Animal feed such as pellets consists of 3 percent nitrogen.
It serves as a great fertilizer for horticulture crops.
It contains growth factors that help supply the mineral content to plants as nutrients.
A poultry by-product is feathers.
These contain a high amount of nitrogen up to 7 to 10 percent.
However, they slowly break down to release their nitrogen content.
Kelp Meal, Fish Meal and Blood Meal For Raising Nitrogen Levels
Dried raw seaweed helps improve fertility as it contains 1 percent nitrogen, 2 percent potassium and many trace elements.
Seaweed fertilizers originate from kelp.
Kelp meal can mix with other fertilizers or you can apply it directly to the soil.
Another animal by-product is a fish meal which contains about 10 percent nitrogen and 6 percent phosphate.
This is applied as a fertilizer and may contain stabilizers and preservatives.
It contains a high amount of nitrogen which can even burn the plants with ammonia, resulting in fungal growth and loss of nitrogen.
The nitrogen content is 12 to 13 percent hence, it should be used moderately and carefully.
It is essentially a dried slaughterhouse waste product.
Plants store nitrogen in their stems and roots.
It is crucial for growth.
Some of these plants take up nitrogen and also increase its amount in the soil.
Legumes for instance beans and chickpeas are especially good in taking up and serving as organic material.
Your plants will lack nitrogen if their leaves turn yellow and will have a good supply of it if they remain dark green.
Phosphate and Potassium Sources
Application of organic phosphate should be done a year prior to when the growing cover crop needs the nutrients.
This allows the microbes in the soil to convert insoluble phosphate into a stable form over time.
Mineral phosphate is present in the form of colloidal phosphate present in clay, hard rock phosphate present in volcanic deposits and soft rock phosphate in ancient sea deposits.
Clay phosphates are the most abundant and available.
The bone meal consists of 27 percent phosphate that plants and soil can directly use.
Though, you cannot use rock phosphate directly.
Add it to manure where the acids can dissolve the phosphate and in return that will stabilize the nitrogen.
Or you and add 50 pounds of it to a ton of manure while composting.
Potassium sulfate and potassium magnesium sulfate are potassium sources.
Potassium sulfate is more suitable for soils that already have a high magnesium content.
Granite dust is an organic source with 1 to 5 percent potassium.
However, it is highly insoluble, hence most of this potassium content is not available to the plants.
Glauconite mineral contains 7 percent potassium content.
Though, its high nutrient content releases slowly.
Balck mica also contains potassium which is more easily available than from rocks.
Improving Soil Fertility Using Liming
Lime and Gypsum help to provide calcium to the plants and also moderate the pH of the soil.
In fact, gypsum also delivers sulfur which is crucial to the plant’s growth and for the animals that feed on the plants.
Liming helps to maintain the optimum pH of the soil which is around 5.5 to 6.5.
This maintains soil fertility.
Heavy soils require an application every 3 to 4 years.
The results show in about 3 years after which you should test the pH of soil.
Apply it 8 weeks before planting and sowing and use small quantities to prevent over liming.
It provides phosphates and calcium to the crops.
Liming also helps to prevent the accumulation of aluminum and manganese.
It helps neutralize the acidic soil to reach optimum pH.
Hence, crop production increases.
This leads to food security and more crop yields.
Additionally, it is cheap.
It facilitates the action of fertilizers.
Furthermore, it prevents molybdenum, calcium and magnesium deficiency.
It also brings improvement in the structure of heavy soils.
It facilitates the rotting of organic matter.
Thus, it helps to release nitrogen, phosphorus and potassium into the soil.
Moreover, it promotes earthworm activity which converts organic material to organic fertilizers.
Hence, liming is essential to maintain pH levels and fertility.
If your plants look yellow and have slow or abnormal growth, they are not in good soil.
Causes of soil fertility decline include soil erosion, over-grazing, climate changes, pollution and lack of arable land because of urbanization.
Hence declining soil health is detrimental for the future of agriculture.
Therefore, you need to implement these methods to make your soil richer to sustain agricultural cropping systems.
This will help in consistently producing crops that taste and look well.
Furthermore, it will help feed animals and humans.
Thus, maintaining soil fertility is crucial for life to the food cycle to function properly.