Op-Ed | How Soil Health Is Promoted Through Traditional Knowledge and Modern Science

Let’s be ecologically and historically honest with ourselves. It’s not a fertilizer crisis we’re facing. It’s a soil health trainwreck brought on by the agricultural inputs industry itself. In the global debate around food security, climate change, and sustainable agriculture, soil is finally receiving the attention it deserves. For decades, mainstream agriculture and policies around agriculture treated soil as an inert medium, ignoring soil biodiversity, both above and below ground. Understanding of fertility has been exceptionally narrow, with recommendations limited to a small number of nutrients supplied by synthetic fertilizers. But this model is now showing strain. Across continents, soil has become increasingly degraded by global supply chains that favor monocultures and chemical inputs, perverse public subsidies, and self-serving narratives and advertisements that claim that industrial agriculture feeds the world (even as it ruins our soil). According to the World Atlas of Desertification, 75 percent of the land globally is degraded, with UNESCO warning that 90 percent of the land surface will be degraded by 2050. Over thousands of years, long before the advent of industrial agriculture, farmers have sought to improve soil to grow nutritious and abundant food. During two days in May 2026, collaborative initiatives from India, Brazil, and Kenya, supported by the Agroecology Fund, shared insights in a conversation circle on soil health management as a climate resilience and food security strategy. From India, organizations described how farmers they worked with faced soils left sterile by years of heavy chemical input use. Brazil’s Cerrado region, a vast, biodiverse tropical savanna, has been degraded by deforestation and monocultures dependent on the extensive use of synthetic fertilizers and pesticides. In Kenya, organizations highlighted declining soil fertility and the loss of beneficial organisms caused by hazardous agrochemicals. These initiatives shared techniques to detect and improve soil biodiversity, including by applying participatory methodologies that value local knowledge. From India to Kenya to Brazil, successful soil restoration is emerging from collaboration between farmers, indigenous practitioners, and researchers. Steve Vanek, a researcher in soil science at Colorado State University, and partner of the Manor House Agricultural Centre in Kenya, said that when farmer groups discuss the difference between good and poor soils, they often identify characteristics that align closely with scientific indicators. Farmers mention soils that are “easy to plough,” not crusty, rich in earthworms, and darker in color—observations linked to aggregation and organic matter. In 2022, the Agroecology Fund joined a donor field visit to a diversified coffee farm on the slopes of Mt. Kilimanjaro in Tanzania. A foundation’s technical staff inquired about the technologies the farmer applied to measure carbon sequestration. The farmer crouched, scraped soil together with his fingertips, balled it in his palm and said, “this is how we know.” Scientific research becomes powerful when it helps explain and strengthen farmers’ observations. It becomes more inclusive and accessible when it doesn’t rely on simplistic or reductionist metrics that may be misleading or onerous for farmers to measure. In Kerala’s Wayanad district, a climate-vulnerable hilly region in southern India, farmers had long grappled with soil erosion, acidity, declining productivity, and the overuse of chemical fertilizers. In response to this, Thanal Trust, an NGO based in the region and part of the conversation circle, established a local soil testing laboratory, generating soil health cards for farmers, and combining findings with field-level training rooted in agroecological practice. Farmers learned about structure, texture, microbial life, mulching, trap crops, green manures, and intercropping. Thanal invested in the farmer-to-farmer approach, working with a group of farmers—men and women—who became soil management experts, testing and validating the practices, and disseminating them within their communities. As farmers observed improvements in their soil, they also scaled up traditional engineering practices on their farms, like mud pot irrigation—a traditional practice where water drips through micro-pores of clay pots to maintain moisture exactly where it is needed. Similarly, the practice of husk burial, where coconut husks are buried in trenches, serves to retain moisture and also provide potassium. Sreelekshmi KJ from Thanal said, “The results were visible not only in yields but also in the soil itself. Organisms such as earthworms reappeared, soil microbes returned, and biodiversity thrived. Fields once described as sterile, lifeless mediums became living laboratories.” In Kenya, the Manor House Agriculture Centre (MHAC) developed accessible soil health tools that allow farmers to test infiltration, organic matter, and biological activity using low-cost materials. Vanek, who is a researcher in soil science at Colorado State University, USA, said their work focuses on “the biological and physical aspects as well as some of the major chemical limitations” in smallholder systems while “building based on local knowledge.” Instead of expensive labs disconnected from communities, MHAC came up with soil health assessment kits for smallholder farmers. These provide simplified methods to test soil health for smallholder farmers, research for development, and citizen science. The laboratory uses 3D-printed troughs, or even simple sieves made from cardboard and old stockings. With these low-cost methods to measure particulate organic matter, farmers are quantifying the food available for the soil-food web. These learnings are enhanced through a Farmer Research Network (FRN) supported by the McKnight Foundation, which brings farmers together to diagnose problems, test practices, compare results, and co-produce knowledge. Farmers rank their own soils, identify constraints, and learn simple methods to assess organic matter, infiltration, pH, and biodiversity. The relationship between scientific research and farming communities is changing in both directions. Farmers are learning from researchers—just as researchers are also learning from farmers. In Brazil, the Centro Ecologico described partnerships with academics from federal institutes to study soils biologically rather than only chemically. Joaquim Martins, a family farmer, noted how their approach seeks to understand the vision and perspectives of farming families on soil health while helping strengthen their management practices. “We conducted a series of interviews with farmers to analyze soils through the lens of their lived experiences, priorities, and local knowledge. The aim was to translate scientific data into the everyday realities of farmers’ lives. It also raises an important question: How can scientific research engage in meaningful dialogue with people’s knowledge systems, and how can we, as scientists, remain self-critical in that process?” he said. The program has engaged 200 farming families on the northern coast of Rio Grande do Sul, Southern Brazil. It has also involved Indigenous communities, who bring their own traditions of soil care and green manure practices, as well as women farmers who are helping share and strengthen local knowledge across the region. Researchers applied the BioAS method promoted by the public Brazilian Agricultural Research Corporation (EMBRAPA) to examine respiration, carbon dynamics, and enzyme activity to compare conventional and agroecological systems. But just as importantly, they conducted participatory interviews to understand how families themselves define soil health: porous soils, moisture, insects, worms, easier rooting, and fewer hard crusts. In other words, scientific research is beginning to respond to farmers’ diverse questions. Some traditional practices long treated as informal are now gaining recognition for their rigor. Alessandra Karla da Silva from CEDAC, in Brazil, described work on “green nitrogen” produced from Gliricidia sepium biomass, a tree legume capable of fixing atmospheric nitrogen and cycling nutrients through biomass. Researchers from EMBRAPA and farmers supported by CEDAC agroecological center, in a co-creation model, are exploring how it can reduce dependence on synthetic nitrogen fertilizers while maintaining productivity. These approaches exemplify that the idea is no longer to choose between modern science and traditional wisdom, but rather how to combine them inclusively, intelligently, and effectively. Simply put, the global soil crisis will not be solved by chemistry and simplistic metrics alone. It requires memory, biodiversity, experimentation, and a trusting collaboration with farmers who know their soils. Articles like the one you just read are made possible through the generosity of Food Tank members. Can we please count on you to be part of our growing movement? Become a member today by clicking here. Photo courtesy of Thanal Trust