Home gardens and fruit trees crucial for nutrition

Fruit and other tree products in home gardens can contribute positively to family nutrition and health, in places where improved nutrition is most needed. According to Katja Kehlenbeck of ICRAF, who presented her research at the FAO’s Forests for Food Security and Nutrition Conference on 13th may.

While Latin America, Asia and other regions have their own nutritional challenges, in Sub-Saharan Africa malnutrition is still widespread and consumption of fresh fruits and vegetables (FFVs) is just 1/3 the WHO’s recommended 146 KG per year and person. Deficiencies in Iron and vitamins A and C is especially problematic in this region.

There are solutions, however. Some indigenous fruit trees, such as Adansonia digitata (Baobab) can provide, through its fruit pulp, far higher levels of vitamin C and iron than commonly fruits such as mango and orange. There is a large variability in levels of vitamin C in fruits of different individual baobab trees – from 150-500 mg per 100g edible portion – but even the lowest figure here is far higher than other fruits Typically, mango and orange only have levels of 28 and 51 mg Vitamin C per 100 g edible portion, respectively.

Cultivating a diversity of fruit trees in farms and Home Gardens can also help cope with the ‘hunger gap’, a period of food insecurity typically occurring before the harvest season of the staple crop. In places such as western Kenya, where the hunger gap occurs from March to May, indigenous fruit trees such as Rhus vulgaris as well as exotic fruits such as jackfruit could provide for nutritional and health needs in this difficult period.

Households benefit from the numerous products and services trees, including fruit trees, can provide. These include products such as nutritious fruits, leaves for vegetables, fuelwood and timber, fodder and medicine. Service functions include shade, improved microclimate, control of soil erosion, diversification and also broader beneficial services such as carbon sequestration.

Homegardens, manifest as complex, mixed agroforestry system around the homestead, are often women managed.

These systems too provide many useful products and services, in subsistence, commerce, sociocultural and ecological terms. Fruit trees are an important part of homegarden systems as confirmed by the high number of fruit tree species found in homegardens. In Sulawesi, for example almost 9 fruit tree species were cultivated on average in a homegarden.

1. Subsistence: Fruits, Vegetables, Spices, Medicine, Staple foods, Stimulants, Timber and Fodder.
2. Commerce: Cash
3. Socio-Cultural: Gifts, Sacrifices, Pride, Pleasure, Aesthetics, Employment, Socialising
4. Ecological. Habitat for wild Flora + Fauna, Pest + Disease control, Nutrient Cycling, Microclimate, Soil erosion.

Despite these multiple benefits, there is underutilization of fruit trees, particularly indigenous fruits, in many regions. In the Nuba Mountains, Sudan, for example, gardeners cultivate the fruit tree Ziziphus spina-christi rather for providing fencing material then for the fruits. In homegardens of Sulawesi, Indonesia, some fruits from homegardens such as pawpaw were fed to pigs rather than consumed by the family.

There are threats to homegardens too. The transformation of traditional mixed home gardens into commercial vegetable gardens, for example in the Nuba Mountains, Sudan, has been problematic. In a policy sometimes promoted by NGOS, donated exotic vegetable seeds have been planted. However, this has led to the cutting down fruit trees to meet the light requirements of the vegetables, as the trees blocked sunlight. This short-sighted policy also can have gender implications: power shifts over to the man of the household, who then sells the vegetables in the market and controls the money the vegetables generate. This can then be spent in a way that isn’t beneficial to the women and children left behind on the homestead, as Katja explains:

Similar problems may occur when commercial cacao/coffee gardens replace the traditional mixed home gardens in Sulawesi.

These is much done, but more research needs to be done to improve the performance of homegardens.

Kehlenbeck pointed out that we need to document production and utilization data for food trees in homegardens to answer key questions:

1. How do they these food trees contribute to family nutrition, and does this change through the seasons?
2. How do they contribute to family income, and how is that income spent?
3. What is the nutrient content of products from lesser known and lesser used tree species?
4. What are the cultural, socio-economic and environmental factors influencing cultivation of food trees and consumption of their products?

She also recommended that year round production of fruit should be targeted by developing fruit tree portfolios which is a combination of species and cultivars with different harvest seasons, and prioritising the domestication of important indigenous species could also prove beneficial. Then, the best, hardiest, most nutritious species and cultivars can be selected and cultivated in a home garden setting.

To take one example: the variability of vitamin levels between different individual Baobab trees suggests research into extensive sampling of baobab trees, characterisation of the fruits’ vitamin content, selection of superior mother trees, propagation of these trees and dissemination of the seedlings to farmers for cultivation – which is the process of domestication.

Kehlenbeck was keen to emphasise that research programmes need to be multi-faceted. For example, cultural factors are an important, sometimes missing link in helping agroforestry initiatives take root. A better understanding of local beliefs and customs can help improve understanding of what works and what doesn’t ,on the ground in the real world outside of the research institutes.

Katja Kehlenbeck’s take home messages are that tree products are important for nutrition that trees in homegardens contribute to family nutrition (directly and indirectly) and that the potential for home gardens is not fully exploited yet.

Dr. Oliver Moore