Dorica Banda | December 18, 2024
News Brief
In Zambia's Mazabuka district, farmer Zukas Moobola has transformed his cotton farm by using biochar, a technique that improves soil fertility. After struggling with reduced rainfall and decreasing yields, Mr. Moobola adopted biochar, which has improved his soil fertility and yields. Biochar is made by carefully burning crop residues, resulting in a coal that can be used to enhance soil structure, water retention, and microbial activity. Mixed with composted manure, it can increase soil fertility. Trained by Solidaridad, 120 farmers across Southern Province are now using biochar, seeing improved crop yields and greater resilience against drought.
It’s a scorching afternoon in Mazabuka district, Southern Province, Zambia. The heat reaches a stifling 36 degrees Celsius. Under a mango tree, Zukas Moobola, 49, wipes the sweat from his brow. For over a decade, he’s grown cotton on his one-hectare farm, but decreasing rainfall has taken a toll on his yields.
Mr. Moobola uses the profits of his farming to support his family. He used to harvest 1,200 kg of cotton per year. But as rainfall diminished each year, his yields plummeted to just 800 kg. He was close to giving up cotton farming when he heard about biochar—a technique that could enhance soil quality and improve crop yields—and decided to give it a try. Now, Mr. Moobola proudly harvests 3,000 kg of cotton from the same plot.
He explains the process: “I dug my first cone pit two years ago and I was told to stop burning the cotton stalks in the field but cut them down and burn them in the pit. The stalks have to be put in at intervals under low heat from the bottom going up , without access to oxygen. I then mixed the biochar with dung from my cattle and buried the mixture in the soil just before the onset of the rainy season.”
Mr. Moobola advises other farmers to take up biochar. He says, “It is cheaper and eco-friendly, and I don’t ever think I will stop using it. All the material is right on our farms, dung, droppings and stalks from our crops. We put an end to burning and instead put back the carbon where it belongs: in the soil.”
Solidaridad, an international civil society organization, has trained 120 farmers in three districts across Southern Province on how to make and use biochar. Biochar is made by burning organic material, like crop residues, in a low-oxygen environment. When applied correctly, it improves soil structure, water retention, and microbial activity, helping crops withstand drought and boosting long-term productivity.
Farmers need a pit or biochar kiln, rake or shovel, water, and fuel like crop residues, to produce biochar. To start, create cone-shaped pit, about 1 metre in diameter, and start a fire in the bottom. As the fire burns more strongly, add more fuel, like the stalks added by Mr. Moobola. Continue adding fuel as it turns to ash, and when the lop layer is white, quench the fire with water. The charred remnants, known as biochar, can be combined with organic materials such as composted manure.
Pamidzai Bota is the regional manager, and she says biochar and soil microbes create a remarkable material that holds the key to unlocking a more sustainable future for Zambian farmers. She says biochar stands out for its high quality and long-lasting impact as its stability enables it to remain in the soil for hundreds or even thousands of years.
She adds, “It is encouraging to see how this new technique is adopted by farmers and the change in their crop health and yield is incredible.” With the enhanced soil structure in their fields, coupled with improved water and nutrient retention, farmers have increased crop yields and are able to generate more income, become food secure and nourish their communities.
Another farmer, Christopher Banda, began using biochar on his soybean fields last year. Previously, his yields had fallen drastically due to poor rains, dropping from eight tonnes to three. After making biochar from maize and soybean stalks, he mixed it with chicken manure and applied it before planting. The results, he says, were remarkable.
Mr. Banda says, “My soybeans were green, lush, and healthy—even with poor rainfall.” He harvested 12 tonnes, more than tripling his previous yield. He adds, “This has been life-changing. With this income, I can now afford to drill a borehole and even grow soybeans twice a year.”
For Zambian farmers, biochar is not only a path to greater yields but also a climate-friendly solution for building resilience.
