Canadian science unlocks an African fertiliser solution with global potential

Food security remains one of the defining challenges of the twenty-first century. Despite advances in agricultural science, hundreds of millions of people continue to experience chronic hunger, particularly in parts of Africa where population growth, climate pressures, economic constraints, and limited access to agricultural inputs undermine crop productivity. A promising new development, enabled by Canadian research infrastructure and African scientific innovation, could help address one important part of this challenge: access to affordable potassium fertiliser.

Researchers from Mohammed VI Polytechnic University in Morocco, working with the Canadian Light Source (CLS) at the University of Saskatchewan, have developed a method to produce fertilizer from potassium-rich local rocks. The approach has the potential to reduce reliance on imported potash, lower costs for farmers, improve nutrient efficiency, and strengthen food security across parts of Africa. While the research addresses a regional agricultural need, its significance extends well beyond Africa. The project represents an example of how international scientific collaboration can generate solutions with global relevance, particularly as nations seek more sustainable and resilient food systems.

Agricultural discussions often focus on nitrogen and phosphorus, but potassium is equally essential for plant growth. Potassium helps plants regulate water, improves resistance to diseases, strengthens root development, and contributes to higher crop yields. Without adequate potassium, crop performance can decline significantly. Many African soils contain considerable organic matter and have favourable moisture conditions. Yet crop productivity can remain limited because farmers lack access to affordable fertilizers that replenish essential nutrients. Potassium fertilizers are often imported over long distances, creating supply vulnerabilities and increasing costs.

The global potash market is concentrated in a relatively small number of producing regions, notably Canada, Russia, and Germany. Consequently, many African nations depend on imported fertilizer supplies that can be affected by geopolitical events, transportation disruptions, and fluctuating commodity prices.

The limitations of conventional potash

Traditional potassium fertilizer offers proven agronomic benefits, but it is not without drawbacks. One challenge is that potassium salts derived from potash are highly soluble. While this makes nutrients readily available to plants, it also means that a significant proportion can leach into groundwater and surface waters before crops can absorb it. Such nutrient losses represent both an economic cost to farmers and an environmental concern. Another issue involves the chloride content found in many conventional potassium fertilizers. Over time, excessive chloride inputs can contribute to salinity problems in certain soils and potentially affect water quality. These challenges have encouraged researchers to explore alternative nutrient sources that are locally available, environmentally sustainable, and economically viable.

The Moroccan research team focused on syenite, an igneous rock rich in potassium-bearing minerals such as feldspars. Such rocks exist in several regions of Africa and represent an abundant but underutilized resource. The difficulty is that the potassium in these minerals is trapped within a highly stable crystalline structure. Although present in significant quantities, the nutrient is not readily available to growing plants. As Professor Abdellatif Elghali explains, the challenge is not the lack of potassium but its limited accessibility within the rock matrix.

To overcome this problem, the researchers developed a treatment process involving crushing the rocks, mixing them with water and either alkaline or acidic agents, and heating the material to temperatures just below 200°C. This treatment alters the mineral structure and transforms the potassium into a more soluble form that plants can access. When tested in water, the modified material released an initial burst of potassium and calcium followed by a slower, sustained release phase. Importantly, the material also supplied other beneficial elements including magnesium and silicon, both of which can support soil health and plant development. Laboratory studies indicated that crops such as corn and soybean could absorb nutrients from the treated rocks at levels comparable to those achieved using conventional potash fertilizers.

The scientific breakthrough was not solely about developing a new treatment method. Equally important was understanding exactly how the process altered the rocks and liberated the nutrients. This is where the Canadian Light Source played a pivotal role. Located at the University of Saskatchewan, the CLS is Canada’s national synchrotron facility and one of the country’s most significant scientific research infrastructures. Every year, more than 1,000 researchers from academia, government, and industry use the facility to investigate questions spanning health sciences, agriculture, materials science, and environmental research.

Using intensely bright synchrotron light, researchers can probe materials at exceptionally high resolution and determine structural and chemical changes that are often invisible to conventional laboratory techniques. According to Elghali, routine analytical methods did not provide sufficient information about the mechanisms involved in releasing potassium from the treated minerals. The synchrotron studies carried out at CLS revealed how the heat and chemical treatments transformed the rocks, providing the evidence needed to validate the process. This highlights an important aspect of modern science. Groundbreaking innovations increasingly emerge through international partnerships in which advanced research infrastructure developed in one country enables solutions to challenges faced elsewhere.

Beyond Africa: a globally relevant innovation

Although the immediate focus is on African agriculture, the broader implications are noteworthy. Many regions around the world possess potassium-bearing rocks but have limited access to conventional fertilizer supplies. Rising concern about fertilizer affordability, supply chain resilience, and environmental sustainability has encouraged researchers to seek alternative nutrient sources. A fertiliser technology based on locally available minerals could provide several advantages including lower transportation costs and associated carbon emissions, and, with crops, improved nutrient retention through slower release.

The work also aligns with increasingly important sustainability goals. Agriculture must feed a growing global population while minimizing environmental impacts. Technologies that improve fertilizer efficiency and reduce nutrient losses may become valuable tools in achieving that balance. The researchers emphasise that larger-scale field trials are still required before the technology can be widely adopted. Real-world farming conditions introduce variables that cannot always be replicated in controlled environments. The manufacturing process must also be optimized to ensure it is economically practical and scalable.

Nevertheless, the findings published in Minerals Engineering represent a significant step forward. The work demonstrates that locally sourced rocks can potentially provide an effective and sustainable potassium fertiliser. Perhaps most importantly, the project illustrates how scientific research can create tangible social benefits. In discussing the study, Elghali emphasized that the true measure of scientific success is not simply publications or citation counts, but the ability to improve lives.