Biochar: A Farmer's Best Friend in Tanzania and Beyond

For over 12 years, the work of the Warm Heart Worldwide projects in Thailand, Kenya and Malawi has inspired many within the biochar community. These efforts spurred the creation of Biochar Life, a public benefit company that has introduced thousands of smallholder farmers to small-batch biochar production techniques that are financially incentivized with Global C-Sink carbon credits. The success of these initiatives has been largely driven by local trainers, who spread the word that “Biochar is a Farmer’s Best Friend.” Recent reports from Tanzania and Malawi further demonstrate biochar's potential to revolutionise farming in Africa.

A New Approach to Biochar in Africa

Despite the proven benefits of biochar, past attempts to engage NGOs in Africa with this technology have faced challenges. The lack of large-scale financial backing has been a major obstacle. There is however a renewed hope for scaling up biochar as a cost-effective solution for African farmers through subsidization of the carbon market.

One such success story comes from Tanzania, where Karimu Tanzania conducted a pilot project in 2023/24 to test the effectiveness of homemade, “artisanal” biochar on local farms. The project aimed to train six pioneer farmers from the Arri and Ayalagaya wards on biochar production and application, offering them an alternative to costly, imported, industrial fertilizers. The results were overwhelmingly positive, highlighting the practical benefits of biochar for smallholder farmers.

Biochar Production and Cost Savings

The six farmers involved in the pilot produced 30 buckets of biochar using corn cobs, which they mixed with 120 buckets of manure to create 150 buckets of biochar-enriched manure (or biochar-based fertilizer). This mixture was applied during planting and again at the 5-leaf stage of maize growth. By using biochar-based fertiliser instead of industrial fertilizers, each farmer saved around Tsh 41,750 (approximately $15 USD) per ¼ acre of maize. Given that the average plot size in the region is 2 acres, this translates to total savings of about $120 USD per family per harvest—a significant amount for smallholder farmers.

Total savings of about $120 USD per family per harvest

Increased Yields and Revenue

Perhaps the most compelling outcome of the pilot use of biochar-based fertilizer was the substantial increase in crop yields. Before using biochar, the average maize yield per ¼ acre was 3.9 bags (108 kg per bag). After applying biochar-based fertilizer, farmers harvested an average of 6.15 bags per ¼ acre, a 57.7% increase. This boost in productivity also translated into higher revenue. Farmers saw their income rise from Tsh 233,777 ($85.6 USD) to Tsh 368,631 ($135 USD) per ¼ acre. The increase in yield, coupled with the cost savings from replacing industrial fertilizers with biochar, significantly enhanced profitability.

Cost Reduction

In addition to increased revenue, the use of biochar-based fertilizer also led to a notable reduction in production costs. For farmers using industrial fertilizers and pesticides, the cost of production was Tsh 142,000 ($52 USD) per ¼ acre. In contrast, farmers who used biochar spent only Tsh 100,250 ($36.7 USD) per ¼ acre—a 29.41% reduction. The combined effects of higher yields and lower production costs resulted in a 192% increase in profit. While the average profit for farmers using industrial inputs was Tsh 91,777 ($33.6 USD) per ¼ acre, those who used biochar saw their profits soar to Tsh 268,381 ($98.3 USD) per ¼ acre.

192% increase in profit for farmers

Expanding Interest and Future Prospects

The success of the pilot project has sparked considerable interest in biochar among neighbouring farmers. The visible improvements in crop yield and cost savings have drawn attention, leading to 580 farmers registering for an upcoming expansion cycle. Many farmers have expressed high satisfaction with biochar-based fertilizer, noting that the results exceeded their expectations.

As biochar continues to gain traction in Tanzania and other regions, it presents a promising opportunity for smallholder farmers to enhance soil health, reduce reliance on expensive fertilizers, and increase their profitability. 

Author: Erick Abala, CBEN Communications Coordinator

Data collected and distributed by Francis Panga, Karimu Foundation