In modern agriculture, soil testing is the most important practise to manage fertiliser application and crop production. Without soil testing, it is very difficult to ensure the right application of fertilisers for the crop and get the optimum yield.
What is soil testing?
The process by which elements such as phosphorus, potassium, calcium, magnesium, sodium, sulphur, manganese, copper and zinc are chemically removed from the soil and measured for their available content within the sample of soil is called Soil Testing. This is an important diagnostic tool for determining the nutrient for plants.
What are the objectives of soil testing?
The Objectives of Soil Testing are:
To evaluate the fertility and nutrient status of soil for providing an index of nutrient availability or supply in a given soil.
Determination of acidity, salinity and alkalinity problems.
To provide a recommendation on the amount of manure and fertilizer based on soil test value and according to crop.
To avoid excess use of fertilizer and to ensure environmental safety.
When crops are harvested, a considerable amount of nutrients are removed from the soil and causes loss of fertility in soil over a long period of time. So, the soil should be tested.
Evaluation of the suitability of the soil for the crop.
Restoration of soil fertility is a key factor for crop productivity, profitability and sustainability.
Fertilization programme must consider crop needs, soil supply, fertilizer use efficiency, the contribution from manures etc.
Time to time evaluation of the inherent soil fertility status is essential for arriving at the crop and site-specific balanced fertilization program to sustain productivity.
To Predict the probability of obtaining a profitable response to and fertilizers.
What are the benefits of soil testing?
Soil Analysis leads to more informed fertiliser decisions, reducing risks in the soil such as soil erosion, soil infertility and degraded lands and increasing farm profitability in the long-term.
Reveals the amount of plant-available macro-nutrients in the soil and where soil nutrients are in the soil profile
Identifies nutrients that could be yield-limiting
Monitors soil health properties such as pH, EC and OC, which affect nutrient availability to crops and thereby yields and profitability
Provides a basis for variable rate application (VRT) depending upon soil and crop.
Supports decisions about fertiliser rate, timing, placement and product.
Improved knowledge of the soil types within the farm to maximise management options.
Maximises in-season responsiveness.
Consequently, it also provides a farm management tool with a potential benefit to the farmer of increased yields, reduced operating costs and superior environmental risk management and it also includes improved crop maturity and quality, higher tolerance to disease and pest damage, and increased growth.
(Video: Benefits of Soil Testing)
Why should farmers get their soil tested?
It informs the farmer of the current health of the farm’s soil and how to improve it Soil fertility is determined by the soil’s biological, chemical, and physical properties. Properties such as structure, soil texture, and colour are visible to the eye. However, it is hard to see the chemical composition of the soil. Therefore, there is a need for soil diagnosis and that’s why soil sampling is critical. Soil tests are used to determine the soil’s nutrient level and pH content. Armed with this information, farmers can define the quantity of fertiliser and the exact type that is needed for application to improve the soil on your farm. This is essential because fertile soils are necessary to grow healthy crops.
Soil test leads to minimisation of fertiliser expenditure Knowing the exact deficiency of soil is experiencing will result in zero wastage of such farm inputs. The quantity and type of fertilisers of crops and soil need prevent farmers from wasting money on unnecessary extra fertiliser application. Moreover, nutrients such as potassium and phosphorus that are part of inorganic fertilisers are very limited resources. Their supply is limited or rather finite; implying that there is a need to be cautious in the usage to prevent a future shortage of such limited resources.
Soil testing results in limited over-fertilisation Applying fertiliser to the soil without knowing the exact and actual nutrient that it needs will lead to over-fertilisation Overuse of fertiliser may be harmful not only to the environment but also it might cause fertiliser burn to the crops. Testing soil prior and receiving informed fertiliser recommendation prevents farmers from applying an excessive amount of fertilisers and minimising the related environmental damages. Over-fertilisation might result in water pollution, nutrient leaching, and irreversible harm to the aquatic life. Just a simple soil test can prevent all these negative environmental effects.
Farmers can easily avoid soil degradation It is estimated from research that each year more than 24 billion tonnes of fertile soil is lost because of erosion which is caused by unbalanced soil management. Furthermore, land degradation directly affects the livelihoods and health of an estimated 1.5 billion people. Soil restoration is a costly, difficult, and time-consuming process. Therefore, better soil management through soil testing is an easier route to take, and application of the right amounts of fertilisers is efficient and financially justified.
Farmers with fertile soils can contribute to feeding the world’s growing population The importance of soil testing has been in existence since the early years. Different types of soils and variation in soil properties are important factors to note in farming. Soil texture, soil moisture, and soil chemistry are determinants of what crops can be grown and how much yield the farm can produce. The current generation puts more pressure on the soil than ever before. There is a need for fertile soils to produce yields that will feed the world’s ever-growing population. Improved soil health implies more crops, potentially closing the world’s food security issues. This will eventually bring a better life to millions of people. Soil testing is the first step in soil management. The activity gives farmers valuable information that helps them improve the soil’s health; healthy soils eventually imply healthy crops!
"Healthy soil is the foundation of a healthy crop and healthy farm."
What are the Soil Testing benefits for Farmers?
Soil testing provides plenty of benefits for farmers. Healthy soil improves crop growth. Farmers can begin testing their soil before harvest season to get a jump on how they can improve their soil. These benefits can help farmers by:
Improving yields and profitability because you are providing necessary nutrients to your crops.
Increasing consistency of nutrient availability across a field.
More uniform crop growth. This also helps individual plants stronger against weeds and simplifies other processes like cultivation and spraying.
More uniform plant maturity. This can help simplify crop harvesting and drying along with improving market quality.
Allowing fine-tuning of which nutrients are most needed. Helping you allocate your fertilizer dollars to those nutrients that will give you the greatest profit increase.
What are the Environmental Benefits of Soil Testing?
Soil sampling can also help the environment. Regular usage can wear out the land on which you grow your crops. The biggest impact soil testing has on environmental benefits mean:
More efficient use of plant nutrients means fewer losses from leaching or runoff into waterways.
Poorly nourished crops leave less plant residue to hold soil in place. Plant residue helps build soil and saves it from wind and water erosion.
Providing the right levels of nutrients helps increase yields and may help reduce the need for intensively farming marginal land.