Fruit and vegetables at a market in Nairobi. Photo by Ninara/Flickr

“The cultivation of edible fruit trees is one of the most beneficial enterprises individual farmers and communities in East Africa can engage in,” said Tony Simons, the Center for International Forestry Research and World Agroforestry (CIFOR-ICRAF)’s executive director, in the forward to a new book ‘Fruiting Africa: Fruit Trees and Shrubs of Kenya’. “Their advantage lies in the dual benefits of being able to be used for both household consumption as well as market sale,” he said.

Indeed, fruit trees play wide-ranging and important roles in food and nutrition security for people all over the world. Fruit contains high levels of vitamins, minerals, and phytochemicals such as antioxidants – all of which are hallmarks of healthy diets and have been shown to reduce the risk of several diet-related non-communicable diseases. 

But most of us don’t eat enough of it: in Kenya, for instance, only 6 percent of people aged 15 and under meet the World Health Organization’s recommendation of 400 grams of fruit and vegetables per day.

Growing fruit is also important for many people’s livelihoods, because it provides cash income and creates jobs. It can also offer smallholder and subsistence farmers something of a ‘safety net’ during dry spells, as trees’ deep roots can often pull up enough water to survive when other crops like maize and beans fail; some fruit trees also provide other useful products like medicines, timber, and fodder for animals. Cultivating fruit trees can also benefit ecosystems through soil improvement, microclimate enhancement, providing habitats and food sources that boost biodiversity, and sequestering carbon.

But these benefits are not yet fully valued or realized in many parts of the world. In Kenya, for instance, “the potential of fruit cultivation and utilization is not fully exploited,” said the book’s co-authors. “This is due to several constraints, such as difficulty in accessing planting material, knowledge gaps regarding tree management, fruit handling and processing, poor marketing and infrastructure, low demand for fruit due to high prices, and lack of awareness on the nutritional value of fruits.”

It’s for this reason that the book was written. It comprehensively outlines key attributes for 49 fruit trees and shrubs found in Kenya (both indigenous and exotic), including common and local names, botanical description and ecological requirements, uses, nutritional composition, harvest season, propagation and cultivation, pests and diseases, and commercial value. For each of the indigenous species, a map is also provided to show the current occurrence of the species and suitable areas for its cultivation.

The inclusion of a large number of indigenous species in the guide was a careful and deliberate choice. Exotic species currently make up the majority of fruits that are grown at commercial scales in Kenya, and indigenous fruits are seldom sold in large volumes – they’re “often considered ‘food for children’ or ‘food for the poor’ and are sold at very low prices,” said the co-authors. 

However, the available data suggests that these fruits’ nutritional values are often higher than those of more common exotic species. For example, baobab (Adansonia digitata) and marula (Sclerocarya birrea) contain up to five times as much vitamin C as their famed exotic vitamin-C-rich counterpart, the orange (Citrus sinensis). 

As such, the authors called for more high-quality food composition data on Africa’s indigenous fruit tree species, so they can be better mainstreamed and scaled for use in the food systems of the future – including by being selected for domestication and included in national dietary guidelines. They also recommended the promotion of a ‘fruit tree portfolio’ approach, whereby a range of species with different harvest seasons are cultivated in one location to ensure year-round food and/or income.

“An important element in the design of portfolios is that they are centred around community participation, based on local knowledge, social values, diets, and gender and generational species preferences,” said Stepha McMullin, a scientist at CIFOR-ICRAF and one of the book’s co-authors. “Communities and their local diversity of species can also be brought into larger initiatives such as land restoration.”

Looking forward, Simons noted that future editions of the publication may soon be necessary to keep pace with the expansion of knowledge in this important arena. “Given the dynamic nature of the team behind this publication we can likely look forward to increased species coverage, greater economic analyses, and more on market differentiation in local, national and international markets,” he said.

Overall, the book demonstrates how the diversity of fruit tree and shrub species in Kenya and beyond provides an opportunity, at different scales, to minimise the impacts to some of the major challenges that communities are faced with – food and nutrition insecurity, biodiversity loss, and climate change. “Harnessing the power of tree species diversity and tree-based food production based on ecological and social suitability can produce multiple wins, supporting nutrition as well as the livelihoods and well-being of people in these communities,” said McMullin. 

This book was developed with funding from the European Commission, The International Fund for Agricultural Development (IFAD), the CGIAR Research Program on Forests, Trees and Agroforestry (FTA) and the Federal Ministry for Economic Cooperation and Development (BMZ), Germany.