This big shrub with its colourful, long-lasting berries and large
leaves with silvery undersides, makes an unusual hedge or background
Much-branched shrub or small tree up to 6 m high. Branchlets with
white, woolly hairs and stout, straight prickles up to 5 mm long.
Leaves elliptic, margin entire, large, up to 250 x 90 mm, softly
textured, dark green, glabrescent, becoming hairless/smooth above,
velvety whitish/silver below; pedicels reflexed in flower, erect
in fruit; large bract-like leaves are often present in the axils
of the stem leaves. Flowers in many-flowered, branched, dense, terminal
corymbs, faintly scented; corolla white, mauve to blue or purple,
15 mm in diameter, anthers yellow.
Fruit a smooth, globose berry, 5-10 mm in diameter, green, ripening
through orange to bright red, finally purplish red, remaining on
the plant for at least six months. Flowers and fruit are often found
on the same plant, even in the same inflorescence. Chromosome number:
2n = 24.
S. giganteum shows some resemblance to the declared invasive
weed, S. mauritianum or bug-tree (luisboom) which is a native
of South America. However, that species has no prickles, has yellow
fruit, and is very densely velvety or felty hairy in almost all
This mostly montane species is widely distributed in Africa south
of the Sahara, from the Cameroon to Ethiopia and down from eastern
Africa to the Cape. It is also indigenous to southern India. In
South Africa it has been recorded from all provinces except the
Free State and Northern Cape. It also occurs in Swaziland but not
in Namibia, Botswana or Lesotho. It is sometimes cultivated in Botanical
Gardens and elsewhere, but is not known to become naturalized. In
Australia it is known as African holly.
Habitat: The healing-leaf tree usually grows in dense to partial
shade in forest margins and clearings, among trees and often on
river banks and in other moist places. It is common in high rainfall
areas, up to 2 000 mm annual rainfall. It can grow on steep or gentle
slopes of all aspects and prefers humus rich, well-drained, brown
or red, sandy or loamy soils, also stony soils. The geology has
been described as granite, Swaziland rocks, middle Ecca sandstone.
Derivation of the name
Jaeger (1985) explains that the genus name Solanum is possibly
connected to the Latin noun solamen, meaning a relief or
comfort, assumed from the palliative effects of the nightshades.
The species name giganteum refers to the fact that the healing-leaf
tree is relatively speaking, a very tall member of the genus Solanum,
where trees are quite rare.
The Solanaceae is an economically important family of about 2 600
species of plants, with its chief centre of diversity in Central
and South America. This family contains many poisonous, medicinal
and edible plants, and also several horticultural favourites as
well as many weeds. Potatoes, tomatoes, green peppers and aubergines
all belong to this family.
Solanum is a large, cosmopolitan genus of perhaps as many
as 1 500 species; about 50 of these species are found in southern
Africa and about 30 of them are indigenous. S. giganteum
belongs to the section Giganteiformia (of the subgenus Leptostemonum)
that Child defined in 1998. This is a group of about ten shrubs
and small trees growing in the forest clearings and savanna of tropical
and southern Africa as well as India and SriLanka. Their most important
common characters are: a dense tomentum, entire discolorous leaves,
small flowers, small red berries. S. giganteum appears on
the official Tree List of South Africa (no. 669.4) and Zimbabwe
Specimens of S. giganteum have been collected in forests,
woodland and grassland at a wide range of altitudes from 5-2 000
m. It can also occur as a weed in disturbed areas. It flowers in
summer from October to April; fruiting specimens have been collected
throughout the year, but mainly from December to July. Larger birds
such as louries, doves and bulbuls feed on the fruit, particularly
in late winter when food is in short supply.
Uses and cultural aspects
S. giganteum is a known medicinal plant, as indicated by
its Afrikaans and English standardized common names. According to
Watt & Breyer-Brandwijk (1962), the leaves were formerly used
as a dressing for festering, open sores: the woolly undersurface
being applied to cleanse the lesion and the smooth upper surface
to heal it. The early Cape settlers also used an ointment (with
fat) of the fresh juice of the berry and leaf for a similar purpose.
Hutchings et al. (1996) record that the fruit is used for throat
ulcers by the Zulu, Xhosa and Mfengu. Various chemical constituents
typical of the Solanaceae have been isolated from this species e.g.
solasodine from the fruit and leaves. The Xhosa and Mfengu use the
berry to curdle milk.
Growing Solanum giganteum
This species is an attractive garden subject, mainly because of
the clusters of bright red fruit. According to Nichols (2002), it
can be used as a background plant in herbaceous borders; also as
part of a hedge where it can be the focal point behind the tangle
of thorny creepers or shrubs that form the bulk and body of the
hedge. Seeds germinate easily when cleaned out of the fruit. Seedlings
grow rapidly and the plant should be fruiting in the second year.
- Child, A. 1998. Studies in Solanum and related genera (6). New
infrageneric taxa for the genus Solanum L. (Solanaceae). Feddes
Repertorium 109, 5-6: 407-427.
- Hutchings, A., Scott, A.H., Lewis, G. & Cunningham, A.B.
1996. Zulu medicinal plants, an inventory. University of
Natal Press, Pietermaritzburg.
- Jaeger, P.-M.L. 1985. Systematic studies in the genus Solanum
in Africa: 1-540. Ph.D. thesis, University of Birmingham.
- Nichols, G. 2002. Add colour and life to your hedges. Farmer's
Weekly, 10 May, Grow: 13.
- Van Wyk, B. & Van Wyk, P. 1997. Field guide to trees
of southern Africa. Struik, Cape Town.
- Von Breitenbach, J., De Winter, B., Poynton, R., Van den Berg,
E., Van Wyk, B. & Van Wyk, E. 2001. Pocket list of southern
African indigenous trees: Including selected shrubs and woody
climbers, 1st abridged impression of edn 4. Briza Publications
& Dendrological Foundation, Pretoria.
- Watt, J.M. & Breyer-Brandwijk, M.G. 1962. Medicinal and
poisonous plants of southern and eastern Africa, edn 2. Livingstone,
Edinburgh & London.
Author: Mienkie Welman
National Herbarium, Pretoria