IZA promotes zinc fertilisers to improve crop yields

Last Updated 1 month ago by Kenya Engineer

With NAMPO Harvest Day 2025 taking place from 13 to 16 May, the International Zinc Association (Africa) is promoting the use of zinc fertilisers to address critical soil deficiencies, enhancing crop yields, and contributing to food security.

“Zinc is a vital micronutrient that plays an indispensable role in crop growth and development,” says IZA Africa Director Simon Norton. “In Africa, where nutrient-poor soils are a common challenge, zinc fertilisers are a powerful tool to improve agricultural productivity and ensure the sustainability of our food systems.”

The journey of zinc fertilisers begins with raw materials such as zinc sulphate, zinc oxide, and chelated zinc compounds. These are derived from mined zinc ores or recycled industrial by-products. The manufacturing process involves blending zinc with other nutrients, granulating the mixture into uniform pellets, and drying and packaging the final product.

“Zinc fertilisers are carefully engineered to maximise their efficiency and ease of use,” explains Norton. “The granules are designed for even distribution and optimal absorption, ensuring that plants get the nutrients they need to thrive.” Surfactants ensure that the zinc ion reaches the right place in the soil to enhance crop growth.

Zinc fertilisers can be applied using several techniques, each tailored to specific farming needs. Broadcast application is ideal for large fields, ensuring uniform distribution but requiring careful management to minimise nutrient loss. Band application is placing zinc fertilisers near plant roots to increase availability and reduce the quantity required.

Quick and effective foliar sprays are often used to address zinc deficiencies in crops showing visible symptoms. Seed coating involves treating seeds with zinc before planting to ensure seedlings have immediate access to this crucial nutrient. Fertigation delivers zinc through irrigation systems for precise control over nutrient delivery.

“Each method has its advantages,” notes Norton. “The choice depends on the crop, soil conditions, and the farmer’s specific goals.” Zinc fertilisers are particularly effective in improving the growth and yield of a range of crops.

Cereals such as wheat, rice, and maize benefit from zinc’s role in grain filling and root development. Legumes, including beans and lentils, experience enhanced nitrogen fixation and improved seed quality. Vegetables and fruits, from tomatoes to citrus, see improvements in yield, quality, and disease resistance. Oilseeds and tubers like soybeans and potatoes gain better growth and resilience.

“Zinc is not just about increasing yield; it is about ensuring the nutritional quality of our food,” stresses Norton. “This is critical in Africa, where zinc deficiency in soils can directly impact human health.”

Addressing zinc deficiencies in African soils has implications beyond agriculture. “Zinc is essential for human nutrition. Ensuring our crops have adequate zinc levels contributes to healthier communities and combats issues like malnutrition and stunted growth.”

Norton also highlights the role of zinc fertilisers in building resilience against climate change. “Healthy, zinc-enriched crops are more resistant to stresses like drought and pests, making zinc a cornerstone of sustainable farming,” he concludes.

Organised by Grain SA, and taking place at NAMPO Park just outside Bothaville in the Free State, the event is one of the largest agricultural exhibitions under private ownership in the Southern Hemisphere, attracting over 82 000 visitors and more than 920 exhibitors from various sectors of the agricultural industry.