In drought-prone Sahel, scientists roll out innovative system for producing vegetables

Referred to as the African Market Garden, the new system will be implemented with about 7,000 small-scale farmers at 100 locations in Niger, Benin, Burkina Faso and Senegal, with the aim of extending the success of 3,000 gardens already established in countries of the Sahel during recent years. Support for the expansion comes from the governments of Israel, Italy, Switzerland and the USA and from the International Fund for Agricultural Development (IFAD), the World Bank, and various international foundations and NGOs.

"The African Market Garden combines efficient drip irrigation to save water, energy and labor with improved crop management to boost farmers' vegetable yields and economic returns," said Dov Pasternak with the Niger hub of the India-based International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), which is supported by the Consultative Group on International Agricultural Research (CGIAR).

"The African Market Garden is a promising technology for smallholder farmers, which builds on a vegetable-growing tradition in the Sahel that dates back at least to colonial times," Pasternak explained. "In recent decades, the demand for fresh tomatoes, onions, hot peppers and other vegetables has grown dramatically, as a result of rapid population growth and urbanization, and this has given rise to vibrant local and regional markets. But traditional vegetable farming has proved unable to keep pace, partly because of inefficient use of water and other resources."

Based on more than 8 years of research in 11 countries, the African Market Garden offers a solution. It benefits women particularly, who handle much of the region's vegetable production and marketing, raising their incomes and enhancing family nutrition in a region where vitamin A deficiency is widespread, Pasternak said.

The centerpiece of the new system is a, low-pressure drip irrigation unit, which is installed in a field that comprises clusters measuring 500 square meters. The African Market Garden drastically reduces one of the main limitations of traditional vegetable growing -- its excessive labor and energy requirements, which account for three-fourths of the operating costs of traditional market gardens, the ICRISAT scientist said.

To irrigate a traditional vegetable garden of 500 square meters using the conventional system takes one man, lifting two watering cans at a time, about 4 hours a day or one woman, lifting only one watering can, about 8 hours a day, compared to just 10 minutes for drip irrigation. Using a solar-powered pump or other renewable energy source to provide water allows further savings and makes the system more sustainable.

The new system uses water more efficiently as well, Pasternak added -- an obvious advantage in this dry region. Despite its limited rainfall, the Sahel does have significant water resources, including the Niger, Senegal and Chari Rivers as well as major aquifers, which could be tapped for irrigated vegetable production. As irrigation is developed, farmers in the region will need to use water more efficiently to avoid the kind of anarchic water scavenging with low-cost pumps that is rapidly exhausting groundwater resources in South Asia.

Researchers have also found a way to cope with the scarcity of another vital resource -- hard cash to cover operating costs. The solution they have tested in Benin and Niger is to organize the market gardens on a community basis -- for example, with women's groups, which share these costs as well as the responsibility for managing water and fertilizer supplies, obtaining extension advice and combating pests and diseases.

In Benin, three women's groups have managed communal market gardens successfully, producing vegetables year-round for the last 3 years, according to a report from the US NGO implementing a project in this country with technical support from ICRISAT. Each woman generates, on average, just over US$200 per year from a plot measuring just 120 square meters. The profits are twice those for traditional gardening, plus the nutritional benefits of having more vegetables in the family diet. Young girls are especially happy with the new system, because they no longer have to spend hours fetching water for irrigation.

In addition to the reduced drudgery for women and lower production costs, community market gardening makes the new system more accessible to farmers by better enabling them to manage the set-up costs. The costs of establishing a garden measuring 500 square meters in a cluster system (including a solar pump and water storage) is $830 -- similar to the cost of establishing a traditional garden of the same size in a cluster system. But with higher revenues from the African Market Garden, groups can pay the set-up costs within about 6 months, compared to 14 months with the traditional system, according to a research paper by ICRISAT scientists.

Community vegetable gardening also facilitates the intensive training and technical backstopping that farmers need early on in adopting the market garden system.

Another requirement for success is a diverse array of improved vegetable varieties that are suited to the quality preferences of local markets and adapted to the high temperatures and other harsh conditions of the semi-arid tropics. ICRISAT is meeting this requirement in collaboration with the AVRDC -- The World Vegetable Center through continuous introduction, selection and breeding of new varieties of about a dozen vegetable species.

Improved locally adapted varieties of okra, tomato and other vegetables resulting from their work are spreading rapidly in Niger and other countries of the Sahelian region.

"For the first time ever, markets in the nation's capital, Niamey, were well supplied with vegetables, especially tomatoes, during the last rainy season," said Sanjeet Kumar of AVRDC. "A new line derived from a local onion variety shows promise, yielding 60 tons per hectare, nearly twice as much as other varieties grown by farmers."

ICRISAT and its partners are training a growing cadre of small-scale seed producers to disseminate high-quality seed of the new varieties. Farmers who adopt them can then maintain supplies through their own production. With a wider diversity of vegetables to select from, farmers can more easily grow them year-round, seizing opportunities for off-season production to maximize income.

In a further effort to diversify farming in the Sahel, ICRISAT scientists are promoting vegetable intercropping with fruit trees. One especially suitable tree species is the Apple of the Sahel, or Pomme du Sahel in French (Ziziphus mauritania), whose apple-shaped fruit possesses ten times more vitamin C than apples and is also rich in iron, calcium, phosphorus and essential amino acids. Another is the Moringa tree (Moringa oleifera), whose leaves have seven times more vitamin C than oranges, four times more vitamin A than carrots, four times more calcium than milk (plus double the protein) and three times more potassium than bananas.

"The African Market Garden has proved its worth. To scale up the system, we need to prevail on governments, the private sector, NGOs and aid agencies to help create the conditions for success -- including better technical support for farmers and more efficient markets for inputs and produce," said William Dar, director general of ICRISAT. "If we act boldly now to transform horticulture in the Sahel, the people of this region can have a far better future than the one they face today," he added.