Balanced Crop Nutrition: Fertilizing for Crop and Food Quality
|Farmers need to be encouraged to prioritize not only N and P, but also to apply K and other nutrients|
|Dr. Patricia Imas, Chief Agronomist, ICL Group, Patricia.firstname.lastname@example.org|
|November 8, 2020|
Every farmer wants to see their crops grow healthily, develop fully, and yield properly in both quantity and quality. To achieve all this, crop plants must have enough of every essential nutrient they need readily available in the soil. A plant that lacks any essential nutrient cannot thrive: the seed may not germinate; the plant may not be able to develop good roots, stems, leaves, flowers or fruits. In extreme cases of nutrient deficiency, the plant will die.
Scientists have identified seventeen essential nutrients to plants. The three main nutrients are nitrogen (N), phosphorus (P) and potassium (K). Together they make up the trio known as NPK. Other important nutrients include calcium (Ca), magnesium (Mg) and sulfur (S). Plants also need small quantities of iron (Fe), manganese (Mn), zinc (Zn), copper (Cu), boron (B), chloride (Cl) and molybdenum (Mo). These are known as micronutrient elements because only small amounts are needed by the growing plant.
Fueling soil fertility
Balanced fertilization, the key for sustainable crop production
The business benefits of balanced fertilization of crops are obvious: with higher yields the farmer makes more profit, with better crop quality the produce is more in demand and may attract a premium price, and with better crop health and resistance to pests and diseases the other costs of production such as pesticides are reduced.
Sharing the science of investing in crop nutrition
There is a need to convince farmers to invest in their soil’s fertility. Farmers need to be encouraged to prioritize not only N and P, but also to apply K and other nutrients. In South Asia, Africa and other regions of the world there is rising incidence of deficiencies of K as well as other nutrients in soil due to unbalanced fertilizer use. As soil fertility degrades, farmers are losing the basis for sustained production and income.
Balanced multi-nutrient supply to crops with Polysulphate
Fortunately, there are efficient and effective fertilizer solutions available to farmers. Polysulphate is a multi-nutrient fertilizer that contains four nutrients, namely sulphur, potassium, magnesium and calcium. It contains 48% SO3 (19.2% S), 14% K2O (11.6% K), 6% MgO (3.6% Mg) and 17% CaO (12.2% Ca), all in sulphate form, with all these nutrients fully available to plants. As well as having a low salt index and a neutral pH it has chloride content that is very low, enabling it to be applied to sensitive crops.
Polysulphate is derived from a mineral called polyhalite, mined in the UK. Being a natural crystal, it has a unique dissolution pattern which means that it releases nutrients gradually after being applied to the soil. Gradual nutrient release reduces the chance of fertilizer being leached (lost from the soil) with rainfall and being an environmental problem. The prolonged availability of nutrients perfectly matches the timing and quantity of nutrients required by a wide range of crops.
Effect of Polysulphate application to tomato crop grown in Henan Province, China
Polysulphate guarantees more complete and efficient fertilization, even in the most nutrient-demanding crops that extract a great deal from the soil. These include irrigated crops such as corn, potatoes, beets, cotton or high-productivity winter cereals such as strong wheat. Vegetable crops and orchard trees also benefit from Polysulphate application in many ways: produce has better color, bigger size, less defects and longer shelf life, as shown in this example of a pineapple trial in Malaysia.
Fertilizers fundamental to global food security
Fertilizers play a critical role in the world’s food security. Ensuring that every crop plant has access to an adequate supply of each essential nutrient at every growth stage, with no over or under-supply, would make the world of difference to global food supplies and farmer incomes.