By Albert Makendenge
Achieving optimal yields is greatly dependent on providing crops with the right nutrition at the right time. Understanding the role of fertilizers and ensuring the correct application can make the difference between profit and loss.
Fertilization is an exact science and no two lands can be treated the same. It is therefore paramount that the farmer understands the different typed of fertilizer, application levels and timing of application before embarking on a fertilizer programme. Crops continually extract nutrients from the soil and this, if not well managed over time, can lead to severe depletion of soil fertility and land degradation.
Fertilizers are generally divided into macro-nutrients (nitrogen, phosphorus, potassium) which are added in quite significant amounts; micro and secondary elements (calcium, zinc, boron) which are applied in small doses to aid the uptake of macro-elements.
For optimal fertilizer usage, the soil type, nutrient levels and yield potential of the crop and area must first be determined. Soil that is well looked after normally has the capacity to provide most nutrients needed and shortages can be overcome by using carefully chosen fertilizers. It is wasteful to apply a nutrient if there is already enough of it in the soil.
A soil and crop-specific analyses should be done to identify any shortages and come up with an effective and appropriate fertilization programme. Best practices in fertilization firmly depend on avoiding under or over application, considering the extent of the effect of fertilizers on important soil micro-organisms, the method of application which determines the efficiency of the fertilizer (either band application or broadcasting) as well as precision farming which ensures that the entire land is fertilized according to the soil analysis and expected yield.
Fertilization, therefore takes a whole lot of planning and analysis to get just the right mix of elements applied at the right time and cannot just be done haphazardly. Getting the fertilization part right is very important to getting the best out of the land and the crops planted on it.