Just like humans, plants need an array of nutrients to grow well. These include carbon, oxygen, hydrogen, nitrogen, phosphorus, potassium, Sulphur, calcium and magnesium.
Nitrogen, phosphorus, and potassium help to build the plant’s structures and produce higher yields, while magnesium and calcium help prevent imbalances, which may lead to growth-limiting conditions.
Fertilisers are produced with these required nutrients in mind. This means that there are nitrogen fertilisers, for example, CAN and urea, phosphatic fertilisers and potassic fertilisers. There are compound or mixed fertilisers and these contain two or more primary nutrients – DAP and NPK.
Nitrogen fertilisers are mainly used for maize, wheat, rice and soybean, phosphatic fertilisers are used for maize, cotton, rice soybean and wheat, while potassic fertilisers are used for maize, cotton, peas, rice, soy, tomatoes and oil palm.
Like humans, when any of the nutrients is missing, plants show signs of deficiency. For example, when a plant lacks nitrogen, the leaves will turn yellowish and will have stunted growth.
When it lacks potassium, the leaves will become yellowish between the veins. When it lacks phosphorus, the leaves will turn reddish/purple and stunted growth. Most of the time, failure to get the expected yield is a result of wrong choices by farmers.
