Local Innovations Using Traditional Vegetables to Improve Soil Quality A frican traditional or indigenous veg- were considered traditional vegetables etables are becoming increasingly known for at least two reasons. for their importance in providing food se- 1. While some of these plants were NotesKI curity to millions of Africans in rural and cropped, others were readily avail- urban areas (Rubaihayo 2002). Some have able and harvested in their natural been attributed with having medicinal habitat, lending some support to the properties. However, little is known about idea of their "indigenousness", al- their other properties and their impor- though strictly speaking, many are tance in African agriculture. In June 2002 a found worldwide. team of ten Ugandan and South African re- 2. Many of these plants had been con- searchers began research, using RRA and sumed for countless generations, sig- PRA tools, on the use of indigenous knowl- nifying their importance in local cul- edge in producing and consuming tradi- ture. In some instances, the fruit, tional vegetables in eight parishes in leaves and roots of a plant were con- Uganda. During the fieldwork, researchers sumed. noted that some farmers actively innovate During the colonial period, farmers had http://www.worldbank.org/afr/ik/default.htm using the local resources at their disposal started producing crops such as coffee, in attempts to improve their crop produc- oranges and pineapples for commercial tion. Often these innovations were used to purposes. Parish farmers reported that compensate for the lack of modern agricul- the Amin regime encouraged African tural inputs, such as fertilisers and pesti- farmers to produce exotic vegetables cides. Two examples of local innovations, for commercial purposes. This practice by farmers in a parish situated some 50 km still continues and farmers indicated west of Kampala, that attempt to improve on a trend-line that the cultivation of soil quality by using traditional vegetables exotic vegetables as a cash crop is con- No. 79 are discussed here. April 2005 IK Notes reports periodically on Commercialisation Indigenous Knowledge (IK) initiatives in Sub-Saharan Africa and occasionally Prior to the 1970s, parish farmers predomi- on such initiatives outside the Region. It is published by the Africa Region's nantly produced traditional vegetable Knowledge and Learning Center as crops for home consumption. At that time part of an evolving IK partnership between the World Bank, communi- local farmers did not produce exotic veg- ties, NGOs, development institutions etables, such as cabbages, carrots, lettuce, and multilateral organizations. The etc. which were produced on plantations views expressed in this article are those of the authors and should not be World Bank and mainly consumed by the European and attributed to the World Bank Group Asian populations, or exported. The veg- or its partners in this initiative. A webpage on IK is available at // etables that the rural African population www.worldbank.org/afr/ik/ produced for consumption as local foodstuff default.htm 2 tinually increasing, with more and more land allocated for scarce. The political turmoil and subsequent conflicts that their cultivation. occurred in Uganda during the three decades after indepen- Since independence in 1962, the number of people living dence had decimated the livestock herds in this parish. in Kampala and other urban centres has increased. Most of Farmers reported that although they were busy rebuilding these new urban residents came from the rural areas. Their their herds, the numbers of livestock were extremely small. presence brought about a demand for traditional vegetables Consequently, manure was scarce and a more readily avail- and resulted in a number of popular varieties being grown as able local alternative was required. cash crops for the urban markets. This demand was directly The farmers indicated that besides using manure, the peri- related to migrants' preferences and the lower prices odic resting of soil was a good strategy to follow to maintain charged for traditional vegetables in comparison to prices soil quality and to restore nutrients. However, they seldom charged for exotic vegetables. Rubaihayo (2002) indicates practised this method because of their intensive farming sys- that these vegetables are also in demand as a result of their tems and the need to maximise the use of their small pieces ability to supply consumers with significant amounts of vita- of land (typically between one and two hectares). After min A, B and C, proteins and minerals that are needed for planting exotic vegetables in the 1970s, a number of farmers normal growth. This is vitally important as most of these tra- had investigated ways to improve the soil without involving ditional vegetables are grown by poor rural households or are any resting period. During the fieldwork in this parish, local cheaper to purchase in urban areas in comparison to exotic farmers indicated that the cultivation of traditional veg- vegetables, making them an important source of nutrition etables provided benefits to local soils. for the most vulnerable members of the population; the rural and urban poor. Soil improvement innovations In this particular parish, the farmers grew the traditional vegetables Nakati (Solanum aethiopicum), Ebugga Through a process of experimentation, farmers found that by (Amaranthus dubius), Entula (Solanum aethiopicum gilo) reworking organic plant matter into the soil after harvest, and Ejobyo (Cleome gynandra) as cash-crops. A host of other they improved the nutrient content of the soil, demon- traditional vegetables were grown for household consump- strated by the fact that vegetable crops planted in soil in tion; at least twenty types. Along with exotic vegetables, which organic matter had been reworked had a higher yield the proportion of land allocated for traditional vegetables than the same crops planted in soil in which no organic mat- that have a commercial value has steadily increased since the ter had been reworked. After further experimentation, the 1970s, although exotic vegetables with their premium prices farmers concluded that when the organic matter of tradi- have greater land allotment. tional vegetable crops was reworked into the soil, the subse- quent yield was greater than when organic matter from ex- otic vegetables or other crops was worked into the soil. Minimal resources However, farmers realised that some harvesting practices Despite selling their exotic and traditional vegetable cash- (the uprooting of the entire pant, as opposed to the picking crops at the market in Kampala, most farmers in the parish of the fruit and leaves) reduced the availability of sufficient indicated that they did not have enough money for agro- organic matter so they needed an alternative solution for chemical inputs, such as fertiliser, pesticides, herbicides and some crops. fungicides. The bulk of their income was spent on educa- Farmers pointed out that they rotated various exotic veg- tion, health services, groceries and other commodities that etable crops with traditional vegetable crops because they were not produced in the parish. The few farmers who could observed that the former crops grew better when this was afford to purchase and apply agro-chemical inputs did so spar- done. Experimenting with crop rotation led farmers to be- ingly and predominantly for exotic vegetables. This resulted lieve that this activity provided benefits to the soil and im- in farmers having to rely on local resources to perform simi- proved the yields of crops planted in such a fashion, in com- lar functions as the agro-chemical inputs. However, manure, parison to when crops were not rotated. Further experimen- which is often used as a substitute for chemical fertilizer, was tation led the farmers to conclude that by rotating specific 3 exotic vegetable crops with specific traditional vegetable Some lessons crops, the result was that the exotic vegetable crops grew better and produced a higher yield in comparison to when A few significant lessons can be drawn from the farmers' ex- they were planted in soil that had not previously hosted the periments to improve their soil quality: specific traditional vegetables. Local farmers gave the ex- · Traditional vegetables are an important resource in pro- ample of rotating green beans (Phaseolus vulgarus), Ebugga moting food security and also in maintaining soil quality (Amaranthus dubius), and tomatoes (Lycopersicum ensuring that agriculture can continue to contribute to- lycopersicon) in this order because the Ebugga seemed to wards food security; add beneficial properties to the soil that made the other two · By means of experimentation farmers are able to identify crops grow better. Farmers believed that Ebugga neutralised important properties of both traditional and exotic veg- the soil when it was planted after the green beans, thereby etables that make combined production mutually benefi- preparing the soil for the tomatoes. They pointed out that cial, while improving soil quality; some exotic and traditional vegetables extracted nutrients · Often-expensive modern agricultural inputs do not prevent from the soil, which are essential for the continued optimal farmers from farming effectively and producing market- growth of these crops. The rotation of specific traditional able crops, in fact it encourages them to innovate using and exotic vegetables seemed to replace lost nutrients, re- local resources; sulting in good yields in comparison to when no such rotation · Farmers continually innovate to solve problems. In this pattern was practised. In some cases, the exotic and tradi- case farmers could improve the soil by ploughing in or- tional vegetables aid one another's mutual development and ganic matter but when organic matter was scarce an alter- native method, crop rotation, was identified through optimal growth. means of experimentation. · While farmers did not have any formal networks for sharing Sharing innovations knowledge, exchanges between friends, neighbours and family seem to be effective, as those farmers who attended Parish farmers pointed out that they had no formal network the workshops indicated their awareness and use of these or farmers' association and therefore had no formal means of and other practices. sharing agricultural information. However, they agreed that agricultural information, including innovations such as those described above, was shared informally. Typically, a farmer Future steps would share information with a neighbour, family members Given the focus of this study the researchers were unable to or friends who would in turn share this with their neighbours, work with the farmers over an extended period of time in family members and friends. The presence of an extension order to scientifically verify the actual ability of the identi- officer in the parish, who occasionally convened meetings fied crops to do what the farmers claimed. With regard to with farmers, provided them with an opportunity to share the crop rotation system described previously, amaranthus information. Some farmers indicated that they had shared sp. is known to have some allelopathic effects on other crops information with farmers from other parishes and districts whereby its presence in the soil has a direct effect on the soil when they met at the Kampala market. The farmers who at- nutrients and thus on the crops planted in the succeeding tended the workshops convened for the purpose of this study season; depending on the crop, these effects can be positive indicated that they were all aware of the benefits of the two or negative. Amaranthus sp. are also known to suppress methods of improving soil quality. Women residents were root-knot nematode populations (a major pest for tomatoes) intrinsically involved in agriculture, usually supplying most in the soil. It is clear that farmers observed the effects of the of the labour. They reported that they often shared agricul- different plants on one another, but what is not clear is what tural information during meetings with other women who is actually happening in scientific terms ­ are the crops act- belonged to the same social groups or clubs. ing as a fertilizer or a pesticide (biofumigation)? Given that most of these traditional vegetable crops are grown in many 4 other parts of Uganda (Rubaihayo et al., 2003) and also in a References: number of countries in sub-Saharan Africa (Chweya and Eyzaguirre, 1999) such a verification process is necessary so Chweya, J.A. and Eyzaguirre, P.B. (Eds.) 1999. The that, if warranted, the results can be replicated in these ar- biodiversity of traditional leafy vegetables. Rome: Interna- eas, if local farmers are not already using these techniques. tional Plant Genetic Resources Institute. Parish residents pointed out that agricultural extension Rubaihayo, E.B. 2002. The Contribution of Indigenous Veg- services only reached them during the mid-1990s and that etables to Household Food Security. IK Notes 44, May 2002. parish farmers had developed and still continued to develop Retrieved November 26, 2004 from the World Wide Web: a number of strategies to improve their cultivation of tradi- http://www.worldbank.org/afr/ik/index.htm tional and exotic vegetables. These and other innovations Rubaihayo, E.B., Hart, T.G.B., Kakonge, E., Kaaya, A., developed by local residents need to be identified and their Kawongolo, J., Kabeere, F., Mugisha, J., Tumwiine, J. and usefulness verified. Researchers can then consider how they Rubaihayo, P. 2003. Development of Mechanisms for sustain- can collaborate with farmers to improve on these local inno- able production and utilisation of Indigenous Vegetables and vations. However, local innovations should not be regarded management of their genetic diversity in Uganda. Unpub- merely as parts of a stock of knowledge that can be extracted lished report sent to the McKnight Foundation, Washington, and simply moved to another site or transferred to another USA. group of farmers. The broader study indicated that the use of many vegetables and the manner in which they were pro- duced involved various rituals and social taboos. Ignorance of these could make the innovations impractical when they are exchanged or "improved" upon by outside agents. This article was written by Tim Hart, Senior Research Manager at the Human Sciences Research Council, Private Bag X41, Pretoria 0001, South Africa (thart@hsrc.ac.za). It is extracted from an unpublished report by Hart, T, Abaijuka, I, Kawongolo, J, Rubaihayo, E, Kakonge, E & Mugisha, J (2002) "The Identification and Recording of Indigenous Knowledge using Rapid Rural Appraisal Techniques: The cultivation and utilisation of Indigenous vegetables in the Mpigi District, Uganda." The author acknowledges the contributions of the Ugandan researchers from the National Agricultural Research Organisation and Makerere University, Kampala.