The economics of low pressure drip irrigation and hand watering for vegetable production in the Sahel

Abstract

Low pressure drip irrigation is being promoted in Sub Saharan Africa as an alternative to traditional methods of small scale irrigation of vegetables. The African Market Garden (AMG) is a horticultural production system for smallholders based on low-pressure drip irrigation combined with an improved crop management package. The agronomic and economic performance of the AMG is compared to two gardens irrigated manually with watering cans. One of these gardens is managed according to the same improved crop management package as in the AMG, this treatment is called Improved Management (IM). The other garden is managed according to common practices of vegetable producers in the area, this treatment is called the Farmer Practice (FP). Crop productivity, labor and water use were monitored for two vegetable species (okra and eggplants). The experiment was performed on-station in Niger on three adjacent 500 m 2 plots in a sandy acid soil. It was found that improved crop management practices greatly enhance crop productivity over traditional methods at comparable production costs. The AMG gave higher crop yields and higher returns to investment than the treatments irrigated with watering cans. Labor accounts for up to 45% of the production cost in vegetable gardens irrigated by hand, where 80% of the producer time is spent on irrigation. The total labor requirement for the drip irrigated AMG was on average 1.1 man hours per day against 4.7 man hours per day for the Farmers Practice on a 500 m 2 garden. Returns on labor are at least double for the AMG against the other treatments. The returns on land from eggplant were found to be US$ 1.7, 0.8 and 0.1 per m 2 for the AMG, IM and FP respectively. The returns on water for the cultivation of eggplant are around US$ 2 per m 3 in the AMG, against US$ 0.1 in the Farmers Practice. This experiment showed the strong positive impact of drip irrigation and improved crop management practices on profits at minimal environmental costs, indicating that transformation of existing practices poses a considerable potential towards sustainable agricultural development.

The case for distributed irrigation as a development priority in sub-Saharan Africa

“…These systems ranged in size from 80 to 500 m 2 (for individual farmers) and up to several hectares in communal and cluster configurations. Although little analysis has been done to assess the effectiveness of the more than 2,000 systems installed, one controlled field trial of the AMG in Niger compared it to traditional practices and showed dramatically increased returns on labor, land, and water, as well as improved yields, especially during the long dry season (29). Throughout Niger, farmers who turned to drip irrigation kits and better management techniques to begin producing higher-value vegetable crops often used their new income to invest in labor-saving motorized pumps and to expand their businesses (30).…”

Water and Fertilizer Use Management for Improving Smallholder Farmers’ Tomato Production in the Dry Savanna Agro Ecology of West Africa

“…Low-cost drip irrigation (LCDI) has emerged as a means to address these challenges through increased water use efficiency, labour savings, and higher economic returns (Ngigi et al, 2005;Polak et al, 2003). A recent study (Woltering et al, 2011) quantified the time savings and economic gains associated with drip irrigation for smallholders. Fertilizers should be applied in a form that becomes available in synchrony with crop demand for maximum utilization of nutrients from fertilizers to enhance productivity (Boyhan et al, 2001).…”

Effects of drip irrigation promotion policies on water use and irrigation costs in Valencia, Spain

“…The capacity of localized irrigation systems to reduce consumption on agricultural land without undermining the provision of the water requirements needed by the crops has been widely demonstrated under laboratory conditions and on experimental plots. From Swaziland sugarcane (Merry, 2003) to Turkish olive groves (Çetin et al, 2004), from Uzbekistan cotton (Ibragimov et al, 2007) to Sahel market gardens (Woltering et al, 2011), the world is full of successful and promising examples of drip irrigation development. [AQ3] in Argentina.…”