Rethinking Food Systems: The Pivotal Role of Agricultural Lime in Tanzania Agricultural Transformation

*SAGCOT Soil Health Partnership

By Anthony Muchoki

A dynamic transformation is taking place in various regions of Tanzania, and the AGRA Country Manager Vianey Rweyendela acknowledges that the multifaceted implementation of GAIA by different partners is making a significant impact. He commends the collaborative efforts and diverse approaches taken by various partners involved in the Guiding Acid Soil Management Investments in Africa (GAIA) for their positive contributions to this transformative shift in Tanzania’s agricultural landscape.

The SAGCOT Soil Health Partnership, under the umbrella of GAIA, is instigating a vital shift in traditional farming practices, aiming to rejuvenate the soil and enhance crop yields through rigorous field trials and knowledge-sharing initiatives.

One of their notable initiatives is the short gun trials plot for maize, launched in 2022, which has generated profound results, altering the traditional farming landscape and enhancing crop yield. Farmers like Kulwa Mkwabi were struggling with the harsh realities of agriculture when the partnership started its work in Geita. “Since 2018, I have been cultivating maize,” Mkwabi recalls. “But the condition of our soil has been so poor that without fertilizer, it is nearly impossible even to get a bag of maize. Previously, if you cultivated one hectare, you could barely get a bag of maize; it was a struggle.”

In response to this critical situation, the SAGCOT Soil Health Partnership, a collaboration of SAGCOT and TARI under GAIA, introduced a novel approach to improve soil health, thereby increasing Productivity.

Mkwabi’s fields were part of this innovative project. The team applied lime to their trial plots while Mkwabi cultivated his fields traditionally. The difference was stark. “I firmly believe in the power of lime,” Mkwabi shares. “Because when I look at the maize cultivated here by the experts and compare it to mine, there is a considerable difference. I need the government to bring me lime; my soil will flourish with just lime.”

Mkwabi spoke about her experiences in maize farming since 2018 and how she had seen her soil’s fertility decline. “Our soil condition has gotten so bad that without fertilizer, you can’t even get a bag of corn,” she revealed.

Comparing her previous methods with the recent ones she learned from the SAGCOT and TARI initiatives, she shared her optimism. “The corn planted by the experts and me side by side is an example of the significant difference. They irrigated with lime while I merely tilled the soil. I firmly believe that lime works, as there is a substantial difference when comparing the corn grown by the experts and the corn I grew. My plea to the government is to provide us with lime. I am excited once my land has received lime because I believe that will mark the beginning of improved harvests.”

Mkwabi, voiced her  concern about the financial aspect of the agricultural lime. “The only issue now is the cost. I want the government to provide us with the agricultural lime. Once my soil receives it, it flourishes! I can deal with the other problems but need help with the lime and fertilisers.”

“I would like this soil testing procedure to continue..”

Another farmer, Paschal Lufulila, echoes Mkwabi’s sentiments. He shares his transformation journey from not using fertilizer and practising mound cultivation to the shift towards flat cultivation and systematic planting. This change was inspired by the methods employed by the TARI team.

“I’ve discovered the importance of lime in treating the soil so that when fertilizer is applied, it can effectively nourish the plant,” Lufulila explains. “I would like this soil testing procedure to continue, and I call upon my fellow community members to come forward, get our fields tested, and understand the type of fertilizer and lime we need to use.”

Lufulila, described the transformation in his farming practices, “In the past, I didn’t use fertilisers; I just cultivated my land. But when TARI came, I saw how they ploughed using oxen and how they sowed using ropes. I have also changed my ways; I no longer use mounds, plough with oxen, and sow using ropes. I’ve understood the importance of agricultural lime in treating the soil so that the fertilisers can work properly and the crops can get their nutrients correctly.”

Naomi Bakari Abdallah, another local farmer, sees the main challenges as a need for more capital to purchase fertilizer and a lack of guidance. However, with the knowledge acquired from the SAGCOT initiative, she feels confident that her crop yields will increase significantly if she can get the capital for fertilizer and lime. Abdallah calls for more guidance and support in her farming efforts. “The challenges I face in my farming are due to lack of capital to get fertilisers and lack of direction. Today I have been given direction. The only challenge is capital. If I get capital, I will get fertilisers and lime. I believe my crops will become good, and I will cultivate according to what I have learned.”

Tanzanian Farmers Witness Dramatic Yield Increases through Conservation Agriculture and Soil Health Practices

The Farm for the Future, a commercial farming  initiative, joined hands with SAGCOT in the Soil Health Partnership. Lisa Kibwana, a Nutrition Specialist with Farm for the Future, shared the stark contrast in yields following the adoption of these practices.

“We used to obtain 3 tons of food corn per acre. But now, after applying conservation agriculture and learning about soil health, we get 6 tons. This is twice the yields. And in seed corn, yields have increased from 1 ton to 4.5 tons per acre,” said Kibwana.

While increased yields are a clear benefit, Farm for the Future prioritises knowledge-sharing on soil health management. Farmers undergo comprehensive training, equipping them with crucial skills to understand their soil’s health before diving into agricultural activities.

“A farmer has to perform soil health analysis before doing anything. Through the demo plots, we provide practical training and theory, aiming to empower farmers to replicate our strategies. The ultimate goal is scaling up and adopting conservation agriculture and soil health management,” Kibwana explained.

Farmers participating in the initiative, such as Tahiya Chusi of Ilula Sokoni village in Iringa and Suzana Mhagama from Ngosi village in Kilolo District, have already seen tangible improvements in their agricultural practices and outcomes.

Chusi detailed her experience: “After applying agricultural lime for the first time in 2020 and observing improvements, I applied it again in 2021. Soil nutrient uptake increased in limed soil, leading to better plant growth and increased yield. I went from harvesting 12 to 18 boxes of tomatoes to 35 boxes after lime application.”

For Mhagama, the initiative has also highlighted the importance of adhering to good agricultural practices (GAP), “In my quarter acre, I harvest 4.9 bags (each 100 Kgs) compared to other farmers who cultivated 2 acres and harvest 3 bags only. Therefore, we should consider Good Agriculture Practices.”

Yet, there are still challenges to overcome. Abdallah, another farmer involved in the initiative, voiced her main concerns, centred on the need for more capital to purchase fertilizer and the desire for additional guidance.

“The challenges I face in my farming are due to lack of capital to get fertilisers and lack of direction. Today I have been given direction. The only challenge is capital. If I get capital, I will get fertilisers and lime. I believe my crops will become good, and I will cultivate according to what I have learned,” she expressed.

Florence Nkini, Public Relations Officer at Farm for the Future, acknowledged the substantial impact of their partnership with SAGCOT, which has facilitated new connections and collaborations that have significantly benefited the local community.

Kirenga: Aiming for 10 Tonnes per Hectare in Tanzania Maize Production

For the CEO of SAGCOT, Geoffrey Kirenga, the goal has always been clear – to leverage science to provide sustainable solutions to farming challenges. According to Kirenga, the project was initiated nearly eight years ago in collaboration with partners focused on soil fertility enhancement.

“In the southern highlands and other areas that receive a lot of rain, such as the Lake region, Kigoma, Geita, Kagera, and other places, there’s a soil acidity problem,” he explains. “In collaboration with the Ministry of Agriculture and TARI, we have conducted research and found that there are many areas where lime is available and can be produced for agricultural use.”

Kirenga points out that the average crop yield per hectare in Tanzania and much of Africa continues to be low due to a lack of technology utilization and inadequate knowledge. “For instance, in the Iringa, Mbeya, and Songwe regions, maize yield per hectare can reach up to 10 tonnes. However, the average yield for most farmers is only between 1.3 to 2 tonnes per hectare.”

The SAGCOT initiative, according to Kirenga, has led to significant improvements in these metrics. “In Iringa, farmers have been able to increase their yield from an average of 2 tonnes to 7-8 tonnes per hectare,” he elabored.

The CEO of SAGCOT, Geoffrey Kirenga, emphasised the strides made through the partnership. “We started this work approximately eight years ago. We noticed that in the highlands of southern Tanzania and other areas receiving substantial rainfall, like the lake zone, Kigoma, Geita, and Kagera, the soil acidity problem was significant. We collaborated with our partners to develop a project using scientific research to find solutions.”

Kirenga further elaborated, “Productivity in agricultural crops in Tanzania and many parts of Africa has continued to be low. The reason is mainly because there are things we aren’t doing. Many of these are related to technology and understanding what needs to be done for our farmers and people serving the farmers like agricultural experts and researchers.”

Kirenga’s explanation of the gap between potential and actual yield was striking: “In the regions of Iringa, Mbeya, and Songwe, the yield per hectare of corn can reach up to 10 tons and beyond. However, the average yield for most farmers is only about 1.3 to 2 tons per hectare. This difference, from 10 tons to 2 tons, is a significant loss that farmers incur due to not using the appropriate technologies.”

Dr. Mwango:  We Need  Science-Driven Overhaul of Tanzanian Agriculture

On his side, Dr Sibaway Bakari Mwango, the National Coordinator for Soil Research at TARI, explain the initiative’s scientific underpinnings. “When we speak of soils affected by acidity, we mean that such soils will have a lower productivity level,” he said. “High soil acidity is primarily caused by improper soil management, such as farmers applying fertilizers without assessing the health of the soil. This has been a significant problem. Farmers have been using fertilizers on their fields without testing the soil health to determine which fertilizer should be used. Despite the use of fertilizers, many farmers continue to have low yields. The effectiveness of fertilizers is compromised on soils affected by acidity, often by more than 50%. As a result, even if a farmer uses fertilizer, they may not achieve the high yields we hope for. Many produce at a lower level, harvesting only three, five, or seven bags, but they can’t reach above 30 bags, as we would expect.”

Dr Mwango then proceeded to give a visual explanation of their experimental plots. “Looking at our trial field here, we applied the same amount of fertilizer to all plots. In the first plot, however, we did not apply lime (chokaa), and you can see that the corn is stunted and small. In the second plot, even though we applied fertilizer, we also added three kilos of lime, and the difference is visible. However, the quantity of lime added is still too small. Now, if you come to this third plot, we have added 7.5 kilos of lime along with the fertilizer, and the difference is significant. The corn has grown larger and carries a higher yield. When you extrapolate this 7.5 kilos of lime to one hectare, it equals one ton of lime per hectare. Then if you move to our fourth plot, we’ve added 21 kilos of lime along with the fertilizer, and you can also see its effectiveness.”

It is not just the potential of soil treatment with lime to increase pProductivity but also the profound impact of this approach on the lives of local farmers. Five local farmers are interviewed, each sharing their unique experiences and perspectives on the ongoing partnership.

Dr. Bakari continued, “To summarise, we’ve noticed that liming can bring soil health back to optimal conditions, resulting in a massive yield increase. Our trials have shown a dramatic difference between plots with and without agricultural lime, even using the same amount of fertilisers. We believe that the future of Tanzanian agriculture is dependent on the widespread implementation of this approach.”

Dr Mwango, spoke about the acidity in the soil: “When we say the soil is affected by acidity, it means that its Productivity is low, and the misuse of the soil mainly causes this acidity in the soil. For example, farmers apply fertilisers without testing the soil’s health. That has been a significant problem; farmers have been applying fertilisers to their fields without testing the soil health to know which type to use.”

Dr Mwango also pointed out that soil acidity decreases the effectiveness of fertilisers by over 50%, leading to much lower yields than expected. He stressed that adding agricultural lime can significantly improve soil health and Productivity, as illustrated by the experimental plots they had set up.

End