Vitex payos-The “chocolate berry” (black plum) is a tree with round leather-like leaves and fruits which resemble black olives. The strong smelling fruits are surprisingly pleasant to the taste, something like crumbled chocolate.

Vitex payos is a species of hot, low and semi-arid places with high water table. In more arid zones it is found near rock outcrops. The most commonly associated tree species are Acacia polyacantha, Dalbergia melanoxylon, Brachystegia spiciformis etc. It grows from altitudes of 0-1600m, in areas with 650-850mm mean annual rainfall. It can also grow to a height of up to 10m. V. payos often grows in sandy soils, less often clay red and rocky ones. Vitex payos belongs to the Verbenaceae family.

Distribution

Native Range: Kenya, Malawi, Mozambique, Tanzania, and Zimbabwe

Exotic Range: No data

In Kenya, it grows in Semi-arid parts of Eastern, Costal and Central Kenya e.g. Kitui, Embu, Machakos, Kilifi, Kwale, Tharaka, Mberee and Mwingi.

Propagation

Seed germination is hindered by the hard seed coat. This is normally broken by annual fires in the wild; however fresh seeds, germinates more easily. Seeds can be stored at 3-5 deg. C for up to a year. The weight of 1000 fruit stones is about one kg. The tree is propagated by direct sowing of seeds, transplanting seedlings from wildlings, transported either from the bush or from arable land during the rainy season, and root cuttings arising from accidentally or deliberately damaged roots. Many farmers in Kenya do not prefer root cuttings as it results in unstable trees. There has been little success with vegetative propagation using stem cuttings. There is no

literature on grafting and air-layering, suggesting that it has not been tried.

Partial clearing of vegetation is essential before planting out to open up space. Tending should include spot weeding (clearing 1m diameter the space of planted seedling) and slashing until the crop is well established. The tree coppices well.

In Kenya, Flowering takes place during the rainy season (September-December), while fruit ripening occurs during the dry season (April-June). Vitex species generally exhibit hermaphroditism, where both functional male and female organs are in the same flower (Lars Schmidt, 2000). Vitex payos is another Vitex that has received some horticultural exploration. Its woody seed has proven reluctant to germinate, but one method for overcoming this natural resistance is leaving seeds out in the open for a year then knick the end where there are two holes. Trees grow slowly during the first three years in the nursery, but then growth speeds up.

Production

In Kenya, the tree Flowers during the rainy season (October- December), while fruit ripening occurs during the dry season (May-August). Vitex species generally exhibit hermaphroditism, where both functional male and female organs are in the same flower (Lars Schmidt, 2000). The flowers are commonly visited by bees and sunbirds. The growth rate of Vitex payos is moderate; the tree height is from 4-10m. Stones should be sown fresh after removal of the pulp and soaking in cold or warm water for 24 hours. In Côte d’Ivoire, stones dipped into sulphuric acid 95% for 60 minutes and subsequently in water for 72 hours germinated after 26 days, but the germination rate was only 34%. Untreated fruits may take very long (even up to 90 days) to germinate; fire

normally, accelerate germination. Stones may contain several seeds and several seedlings may germinate from one stone. Seeds can be stored for up to 1 year at 3–5°C. Propagation by cuttings has been successful in Malawi. Survival rates in plantations are normally good, about 80–90% after 3 years. In Tanzania fruits ripen in April–July, in Zambia in April– September.

Market Analysis

Vitex payos (Lour.) Merr. These fruits, the “real” chocolate berries, are very popular in parts of southern and Eastern Africa, from roughly Malawi, Mozambique to Tanzania. Zimbabwean villagers are said to collect them in quantity every winter; while in Kenya fruits are collected in July- Angust. Each fruit is about 2 cm long, with pointed tips and a chocolate brown or black skin. The juicy pulp surrounds a single hard stone. However, it is definitely an acquired taste, the powdery texture, the oily mouth feel, and the strong smell. But even then not all is lost: Since 1990, Zimbabwean entrepreneurs have been making jam from the fruit and selling it in the city markets.

In Zimbabwe Vitex payos fruits are sold for 1.5$ per pack (of 30-35 pieces of fruits). In Kenya fruits are sold in Kitui, Mutomo, Mbeere (Ishiara) and also in Dodoma, Singida and Kondaa in Tanzania. In order to increase farmers’ income from Vitex payos fruits appropriate processing technologies for the fruits need to be developed to add value to the products. Research into the development of appropriate processing technology must have emphasis on simple technologies that are appropriate at village level to allow rural people the opportunity to generate income throughout the year, with maximum value added at the village level.

Nutritional value

Nutritional composition of vitex payos (black plum) fruit pulp Per100g of raw edible portion.

Economic importance

Fresh fruits are eaten by human beings, monkeys, gorillas, chimpanzees and elephants, which probably disperse the seeds later. The blackish pulp of the fruits is edible and eaten raw. It is often used to make jam. A beverage is made from the fruit juice, and boiled fruits are the basis for an alcoholic liquor and wine. The seeds inside the fruit stone are also edible. Cooked young leaves are eaten as a vegetable or in sauces.

The wood is popular for house building, vats, furniture, stools, carving, tool handles, gunstocks, bowls, spoons and beehives. It is also suitable for light construction, light flooring, joinery, interior trim, boxes, crates, matches, veneer, plywood, hardboard, particle board, wood-wool and pulpwood. The wood is used as firewood and for charcoal production.

Vitex payos has numerous applications in traditional medicine. Pounded bark is administered to treat threadworm and skin problems. Leaf sap is used as an eye drop to  treat conjunctivitis and other eye complaints. Leaves are boiled and the liquid drunk by patients who have lost their appetite. A Paste of pounded leaves and bark are applied to wounds and burns.

Leaf infusions are added to alcoholic drinks to make them stronger. A root decoction is administered orally to treat stomach problems or gastro-intestinal disorders. Powdered bark added to water is taken to treat colic, and a bark extract is used to treat stomach complaints and kidney troubles. The bark is also used against leprosy, liver diseases, and to control bleeding after childbirth. Dried and fresh fruits are eaten against diarrhea. The twigs are used as chewing sticks for teeth cleaning.

The blackish extract obtained by boiling leaves, bark, roots and/or fruits is used as ink and as a dye for clothes. The flowers serve as source of nectar for honeybees. Cattle browse the foliage as fodder

Services

Shade  or  shelter:  The  heavy  rounded  crown  of  V.  payos

provides good shade.

Nitrogen fixing: The tree has nitrogen-fixing roots.

Soil improver: Leaves can be used for mulch which improves soil fertility.

Boundary/barrier/support:   Grown    in    fields    and    along boundaries.

Challenges

Little has been done to improve the tree propagation methods or growth.

Poor marketing of fruits or jam made from the fresh fruits. Poor germination of seeds after storage-seeds germinate easily when sown fresh.

Way forward

1. Develop propagation methods to shorten fruit maturity,

Improve fruit Production and the growth rate

1. Explore the full potential of this tree
2. Assess the market potential for fruits and other tree products
3. To analyse current marketing practices (including marketing channels, harvesting, storage and processing) of the fruits and fruit products
4. Develop best storage methods which can extend seed life or good germination ability after storage
5. Carry out More research on vitamin content and

Further reading

Patrick M. Maundu, Grace W. Ngugi and Christine H.S. Kabuye (1999) Traditional Food Plants of Kenya. National Museums of Kenya, Nairobi, Kenya

Christopher K. Ruffo, Ann Birnie and Bo Tengnǎs. (2002) Edible Wild Plants of Tanzania. Regional Land Management Unit (RELMA), Swedish International Development Authority (SIDA).

B.O. Muok, B. Owuor, I. Dawson & J. Were. Agroforstry Today 2002 Volume 12 no 1 ‘the potential of indigenous fruit trees: results of a survey in Kitui District, Kenya, pg 13-16

Simitu, P., Jamnadass, R., Kindt, R., Kung’u., J and Kimiywe, 2008. Consumption of dryland indigenous fruits to improve livelihoods in Kenya. The case of Mwingi district. Acta Horticulture (in press).

A. J. Simons, A. S. SAALIM, C. Orwa, M. Munjuga and A. Mutua. 2005. Agroforestree database: a tree species reference and selection guide. World Agroforestry Centre.