Agricultural Development
Senior 6 · Economics
Agricultural Development
Lesson 2 of 4
25 min
In Season A 2026, Rwanda's farmers harvested 488,622 tonnes of maize from 245,001 hectares, an average yield of 2.0 tonnes per hectare. Large-scale farmers alone averaged 4.3 tonnes per hectare (NISR, Seasonal Agricultural Survey, Season A 2026, Tables 6 and 14).
| Share of farmers who, in Season A 2026… | Small-scale farmers | Large-scale farmers |
|---|---|---|
| used improved seeds | 35.2% | 82.6% |
| used inorganic fertiliser | 66.3% | 89.6% |
| irrigated | 12.6% | 60.3% |
| used any mechanical equipment | 0.8% | 24.2% |
Think: the table suggests what large-scale farmers do differently. Which of these differences could a small farmer on half a hectare adopt, and which could not?
Definition
Modernisation approach (improvement approach): raising agricultural productivity by bringing modern inputs, machines and scientific methods into existing farms, without changing who owns or works the land.
Intensive farming: using more capital and inputs (fertiliser, improved seed, irrigation, labour) per hectare to raise yields. Extensive farming: raising output mainly by cultivating more land with few inputs.
Definition
Mechanisation: replacing human and animal power in farming with machines, from improved hand tools and ox-ploughs to power tillers, tractors, threshers and dryers.
Agricultural research develops better seeds, breeds and methods; extension carries them to farmers through advisers, demonstration plots and farmer groups.
| Advantages | Disadvantages |
|---|---|
| Land is prepared and harvested faster, so planting is on time | Machines are costly to buy, run and repair for small farmers |
| Higher labour productivity and less drudgery | Can displace labour where other jobs are scarce |
| Larger areas can be farmed by the same workers | Tractors suit large, flat fields, not small terraced plots |
| Machines for threshing and drying cut post-harvest losses | Fuel, spare parts and machines are imported, costing foreign exchange |
| Makes farming attractive to educated young people | Heavy machines can compact and erode soil on slopes |
On Rwanda's hills, the realistic route is appropriate mechanisation: small power tillers, shared machines hired from service centres, and machines for processing rather than ploughing. PSTA 5 plans to raise the land under mechanisation from 81,711 ha to 100,000 ha by 2028–29 (MINAGRI, PSTA 5, p. 23), and Farm Service Centres to provide mechanisation, inputs and advice (p. 18).
The quickest gains in yield come from improved seed, fertiliser, pest control and irrigation, used together. During PSTA 4 (2018–2024) inorganic fertiliser use rose from 22% to 56% of farmers (from 32 to 70 kg per hectare), improved seed from 9% to 29%, and irrigated land doubled to 71,585 hectares (PSTA 5, p. 8). PSTA 5 aims to raise fertiliser use to 94.6 kg per hectare by 2028–29 (p. 22).
But inputs face the law of diminishing returns: if more of one input (fertiliser) is added to a fixed amount of land, each extra unit eventually adds less output.
Along TP₁, each extra 50 kg of fertiliser adds less maize: 0.8, then 0.5, 0.2 and 0.1 tonnes. Better technology, such as an improved seed that responds more to fertiliser, shifts the whole curve up to TP₂. This is why research matters: without new varieties and methods, adding inputs soon stops paying.
Worked example
Worked example 1: how much fertiliser pays? (illustrative prices, using TP₁)
Maize sells at Frw 400 a kg and fertiliser costs Frw 1,000 a kg, so each extra 50 kg of fertiliser costs francs per hectare.
| Fertiliser (kg/ha) | Yield (t/ha) | Extra maize (kg) | Value of extra maize (Frw) | Worth it? |
|---|---|---|---|---|
| 0 → 50 | 1.6 → 2.4 | 800 | 320,000 | Yes |
| 50 → 100 | 2.4 → 2.9 | 500 | 200,000 | Yes |
| 100 → 150 | 2.9 → 3.1 | 200 | 80,000 | Yes |
| 150 → 200 | 3.1 → 3.2 | 100 | 40,000 | No |
The farmer should apply 150 kg per hectare: up to that point each step adds more value than it costs. The rule is to keep adding an input while the value of its marginal product is at least its price:
If the price of maize falls, or fertiliser becomes dearer, the best amount falls. That is one reason why farmers' use of inputs depends on prices and on subsidies.
The Rwanda Agriculture and Animal Resources Development Board (RAB) breeds and tests varieties suited to Rwanda's altitudes and diseases. In June 2021, for example, RAB and its partners released 19 new bean varieties, 13 of them climbing beans (PABRA, 2021), and with IITA it has introduced cassava varieties that tolerate cassava brown streak and cassava mosaic diseases (IITA, 2020). Extension then spreads them: PSTA 5 plans to raise the number of extension agents from 16,654 to 21,620 by 2028–29 (p. 30). Research without extension never reaches the field; extension without research has nothing new to offer.
Rwanda's main modernisation programme, the Crop Intensification Programme (CIP), began in 2007; land use consolidation followed in 2008 (MINAGRI, PSTA 4, p. 17). The CIP combined four measures: subsidised improved seed and fertiliser, extension, better post-harvest handling, and land use consolidation, in which farmers in an area keep ownership of their plots but plant one selected crop together, at the same time, so that inputs, advice and machines can serve the whole block.
The results were large at first: total production of the CIP priority crops on CIP-supported plots grew by more than 150% between 2007 and 2013. After 2013 further gains were "harder to achieve", and most priority crop yields in 2016 were similar to their 2013 level (PSTA 4, p. 17).
| Strengths of land use consolidation | Weaknesses |
|---|---|
| Economies of scale in buying inputs and selling output | Farmers lose the choice of what to grow |
| Synchronised planting makes extension and pest control easier | One crop per block raises the risk from disease and price falls |
| Larger blocks allow machines and irrigation | Less variety in what households grow and eat |
| Easier links with buyers and processors | Gains fade once the easy improvements are made |
Worked example 2: what would the PSTA 5 maize target add?
PSTA 5 aims to raise maize yields to 2.74 t/ha by 2028–29 (p. 21). If Season A 2026's harvested area of 245,001 ha reached that yield, how much maize would it produce, and what is the percentage increase on the actual 488,622 tonnes?
A 37% rise in output from the same land (a rough guide only, because 2.74 t/ha is PSTA 5's target for whole years, not for Season A alone): this is the case for intensification in a country where almost no new land is left to farm.
Warning
Yield is not production. Production (tonnes) = yield (tonnes per hectare) × area (hectares). Production can rise because more land is farmed while yields stay flat; that is extensive growth. In Rwanda, with little spare land, sustained growth must come from higher yields.
Tip
Modernisation = "MIRE". Mechanisation, Intensive use of inputs, Research, Extension. In an essay, give each one a Rwandan example and a limitation.
Important
Discuss. The CIP raised production quickly, then the gains slowed. Using the law of diminishing returns, explain why. What would be needed to start a second round of gains?
NTV Uganda, "Land Consolidation: Helping Rwanda's rural farmers get the most out of the land" (about 2015). A news report on consolidated plots in Rwanda. Its figures are about ten years old; listen for the reasons farmers give for and against joining.
Practice
Sources and credits
Written by Ganzaa: the text, the total product diagram, the tables, the worked examples and the practice items. The yields and prices in the diagram, worked example 1 and the practice items are illustrative.
