Agricultural experts in Tanzania are encouraging coffee farmers to adopt ground-cover practices to protect their farms and sustain production amid changing weather patterns. The approach, promoted through the Coffee & Climate Toolbox, involves planting suitable vegetation between coffee rows to reduce soil exposure to rainfall and sunlight, conserve moisture, and improve soil structure. This method helps reduce erosion, retain soil moisture, and create a better environment for coffee plant roots.
According to Godfrey Wilgod, Agronomy Coordinator at Hanns R. Neumann Stiftung (HRNS) Tanzania, soil protection is crucial in preparing coffee farms to withstand climate change impacts. Unpredictable rainfall, intense downpours, rising temperatures, and prolonged dry spells are increasingly affecting coffee trees and the soil supporting their growth. Exposed topsoil can be washed away during heavy rainfall, carrying essential nutrients needed for healthy plant development.
Cover cropping, also known as living mulch, involves growing suitable annual or perennial vegetation between coffee rows to shield the ground from direct exposure to sunlight and rainfall. The practice is among the climate-smart agricultural approaches promoted through the Coffee & Climate Toolbox. A knowledge platform developed to provide coffee farmers, trainers, and agricultural extension workers with practical guidance on adapting production to changing climatic conditions.
The Tanzania Agricultural Research Institute (TARI-Uyole) assessed the use of Canavalia ensiformis, a leguminous plant, as a cover crop in coffee fields in Mbozi District, Songwe Region. Preliminary findings indicate that the practice could contribute to improvements in soil fertility, with total nitrogen levels increasing from 0.10% to 0.19% in intercropped areas. Organic carbon and available phosphorus also showed significant improvements.
The assessment also documented observations of improved soil cover and moisture retention among farmers at Pamoja AMCOS. Such observations are relevant to producers facing increasingly unpredictable weather, reinforcing the importance of protecting the soil as part of routine coffee farm management. According to Wilgod, cover crops can help address several soil-management challenges simultaneously, including reducing direct exposure to sunlight and supporting water infiltration.
However, the benefits of cover crops depend on appropriate management, as they can compete with coffee trees for water, nutrients, sunlight, and other resources if not carefully selected and controlled. TARI-Uyole recommends monitoring soil moisture and adjusting planting density and management practices according to local conditions. Further assessment is needed to establish the longer-term effects of cover cropping on soil fertility.
For Wilgod, soil protection should be treated as a continuous investment rather than a seasonal farming activity. The approach is particularly important because cover crops are most effective when incorporated into a broader soil-management strategy, including mulching, compost application, rainwater management, and appropriate nutrient management. The Coffee & Climate Toolbox provides practical guidance on these and other climate-smart approaches to help farmers translate agricultural knowledge into techniques they can apply under their own farming conditions.
Key points
- Coffee farmers in Tanzania are adopting cover crops to protect their farms from climate change impacts and sustain production.
- The use of cover crops can improve soil fertility, reduce erosion, and retain soil moisture.
- Proper management of cover crops is crucial to avoid competition with coffee trees for resources.
