Begonia geranioides is a dainty white, summer-flowering tuberous perennial herb that thrives in shady conditions and makes a good indoor display pot plant.

Description
Begonia geranioides is a tuberous, fleshy, often stemless perennial that grows to about 300 mm tall. The leaves are light green, roundish, heart-shaped (up to 80 x 110 mm), with white hairs and with margins often shallowly and irregularly lobed with blunt teeth. The juvenile leaves are sometimes white-spotted, with veins often pinkish or reddish. The flowering stems are hairy, leafless and held above the leaves at about 300 mm and are also pinkish or reddish. The male and female flowers occur separately (unisexual) but are borne on the same individual plant (monoecious) and can be self-pollinated to produce viable seeds. The pure white blooms, with a yellowish centre, are borne on pendulous stalks, from December to June. The male flowers generally have four tepals and the female five, and both are about 20–30 mm across. The fruit is three-winged and about 20 x 20 mm across the broadest part of the wings.

A.  Male flower B.  Flower bud C. Female flower D. Cross-section through the ovary E.  Habit, reduced.

Conservation status
Begonia geranioides is currently not listed as threatened. However, destruction of habitat could possibly prove to be a future threat.

Distribution and habitat
The begonia family occurs in tropical and subtropical areas, with most species in America (2 genera and over 900 species). In southern Africa there is one genus (Begonia) with five indigenous species: Begonia dregei, B. homonyma, B. geranioides, B. sonderiana and B. sutherlandii subsp. sutherlandii.

Begonia geranioides is largely endemic to KwaZulu-Natal, where it occurs in forests, on rocky, shady cliffs and steep banks, from the coast to 1 375 m altitude inland, from Karkloof, Howick to the coast and Kranskop, up to the Zuurberg in Eastern Cape.

Derivation of name and historical aspects
Begonia is named after Michael Begon, 1638–1710, a French governor of San Domingo and a patron of botany. The specific name geranioides means Geranium-like, referring especially to the leaves.

Ecology
Begonia geranioides is quick-growing and does not like much water in winter as it occurs in a summer rainfall area. It is completely dormant in winter with only tubers remaining to sustain the growth. The tuberous root system enables it to flower and survive even in dry periods.

Uses and cultural aspects
There are no known specific recorded traditional or cultural uses for Begonia geranioides. B. homonyma is used to counteract isiDliso (poison administered in food) and B. sutherlandii is used for heartburn. Both plants are also used as a protective charm.

Growing Begonia geranioides

Begonia geranioides is easyly propagated from seed, as well as tip and leaf cuttings. Cuttings are best taken in midsummer and treated with a rooting hormone. They root easily in river sand or silica sand in an intermittent mist-spray area or in a warm, moist, shaded area.

Hand pollination is necessary for a successful seed harvest in cultivation. Generally, begonias hybridise easily, so care should taken where a number of species are growing in the same area.

Seed is best sown in early spring or summer, in a moist but well drained medium. Once seedlings reach 30 mm they can be pricked out and potted into 120–150 mm pots. We have found success with a well-mixed combination of 40% compost and 60% pine bark medium with a handful of organic fertilizer (Bounceback ®).

In cultivation, under optimum conditions, B. geranioides can flower for an extended period from midsummer to winter.

References and further reading

• Germishuizen, G. & Meyer, N.L. (eds). 2003. Plants of southern Africa : an annotated checklist. Strelitzia 14. National Botanical Institute, Pretoria.
• Hilliard, O.M.. 1976. The Flowering Plants of Africa.
• Pooley, E. 1998. A field guide to wild flowers of KwaZulu-Natal and the Eastern Region. Natal Flora Publications Trust, Durban.
• Hutchings, A., Scott, A.H., Lewis, G. & Cunningham, A.B. 1996. Zulu medicinal plants: An inventory. University of Natal Press. Pietermaritzburg.