Commemorating Michel Bégon (1638–1710), patron of botany and Governor of French Canada.

Mostly perennial herbs and shrubs, occasionally climbers. Stems succulent, woody, or occasionally absent, often swollen and jointed. Roots fibrous, rhizomatous, bulbous or tuber­ous. Leaves alternate, shape variable but mostly asymmetrical, often patterned or coloured; stipules 2. Flowers unisexual in axillary clusters, the males and females next to one another, sometimes double in cultivation. Male flowers with mostly 2-4 segments. Female flowers with 2-5 equal segments. Stamens numerous. Ovary inferior, 3-celled and often 3 winged; stigmas twisted. Fruit a capsule, usually winged, sometimes fleshy and berry-like (some of the trailing epiphytic species from tropical W Africa have spindle-shaped ovaries without wings).

The begonias comprise a large horticultural group of plants with thousands of hybrids and cultivars. The first begonia cultivated in Australia was possibly as early as 1836 although cane-stemmed and semperflorens kinds were well established in the 19th century through both private and commercial importation. Prominent 19th century Australian growers included E. W. Hacket and C.F. Newman, while the Adelaide Botanic Gardens listed 25 species and 11 cultivars in 1855 and 50 species in 1878. In 1979 a small group of people in Adelaide formed the Australian Begonia Society Inc. In 1991 this became the Association of Australian Begonia Societies uniting five states (SA, Qld, NSW, Vic and WA) and the first Australian Begonia Convention was held in Adelaide in April 1988. The formation of this society stimulated interest and during the period 1985-94 230 species were imported as seed, mostly of South American plants, from the American Begonia Society: about 200 of these remain in private collections.

There has also been some field collection, notably recent collections by Bob Cherry (Paradise Plants, NSW) in China and Vietnam, mostly of rhizomatous species, some yet to be identified, and most with distinctive foliage. Other collections have been made by Michael Ferrero in New Guinea. Another recent development has been extensive hybridisation – it would be difficult to estimate the number of Australian hybrids in cultivation today. Private hybridisers include Mr M.C.R. Sharrad, Mrs J. Goodwin and Mr J. Hafer; Mr Ralph Willsmore of Begonia Farm, Myponga, has imported seed and tubers commercially for several years from America and the United Kingdom and has, for 35 years, bred and developed many outstanding tuberhybridas. With the exception of tuberhybridas the number of commercially available begonias is fairly limited and has not changed markedly over the last 15 years as the outstanding hybrids and species remain in private collections: these may only be seen at the state Begonia Society shows and displays.

Ornamental asymmetrical leaves shaped like elephant's ears; 3-angled fruits.

Collections of tuberous begonias may be seen in Victoria at 'Maplewood', Macedon, property of Mr Philip Wright, at Wombat Hill Botanical Gardens, Daylesford, and at Bendigo (conservatory in Rosalind Park). Ballarat holds an Annual Begonia Festival in the new conservatory and has named collections of upright and pendulous varieties of tuberous species and cultivars of Cane types and others. This provides an excellent opportunity to see the different kinds. South Australia has Begonia Farm, property of Mr Ralph Willsmore, Myponga. Displays are held by all state societies during February or March each year. Qld, SA and WA hold competitive shows in conjunction with their usual displays. A listing of Australian cultivars is held by Lyla Kilpatrick and Dr John Mills, c/o Lot 17, Marri Park Drive, Casuarina, WA 6167; superior cultivars are then listed with the international authority (see Appendix 1). Cultivars of tuberous begonias grown in Australia are recorded on database by the Victorian Begonia Society.

Over 1800+ taxa from tropical and subtropical regions, especially America.

Weber & Dress (1968), Haegeman (1979), Thompson, E. & M. (1984), Smith et. al. (1986), Willsmore (1995). Journals: Begonia Australis is the journal of the Association of Australian Begonia Societies. Individual State societies produce information booklets and newsletters. The Begonian is a bi-monthly magazine of the American Begonia Society.

The range of available begonias varies enormously from year to year, making the construction of a practical botanical key impossible. For convenience begonias are classified horticulturally into the following groups and, as these are fairly readily recognised, the species and cultivars are described here within these horticultural groupings. Space permits only a selection of the available cultivars and emphasis is given to the more widely available ones and those raised in Australia.

Cane-stemmed Begonias (Tree Begonias or Angel-wing Begonias): This group is characterised by more or less erect, mostly unbranched bamboo-like stems that have swollen joints. New shoots develop from the base of the plant. The large pendulous flower clusters have a particularly long flowering period. The 'angel-wing' leaves are frequently splashed or spotted with silver and generally have deeply toothed margins. May be easily propagated from tip cuttings and seed.

Thick-stemmed Begonias: In this relatively small group the thick stems that are generally evident only in older begonias are already established in the early growth. The height of the stems can vary and may be of uniform thickness or tapering. Propagation is usually by stem cuttings although a few may be grown from leaf cuttings.

Shrub-like Begonias: Habit shrub-like with a bushy growth habit, stems often hairy and freely branching, new shoots developed from the base. The leaves are variable, sometimes glossy, hairy or felted; the flowers may also be hairy.

Semperflorens Group: This group comprises the bedding or wax begonias available in a range of flower and foliage colour cultivars; they are long-flowering, and in Australia are often grown as annuals although they may be divided and replanted in spring. Grown as annuals they may be established from seed or propagated by cuttings or division. The roots of this group are fibrous.

B. semperflorens-cultorum hybrids (Bedding or Wax Begonia): This group is believed to have been derived originally from crosses of B. cucullata var. hookeri with B. schmidtiana but further species have been added to the hybrid mix including B. fuchsioides, B. gracilis, B. minor and others. Listed commercial bedding cultivars include: ‘Lucy Lockett’, Flowers double pink; ‘Strawberry Sundae’, Leaves pale green; Cocktail Group, Leaves bronze; Devil Group and Olympia Group.

Rhizomatous: This large and diverse group has been subjected to extensive hybridisation producing leaves with a wide range of shapes, colours and surface patterns as well as those with single or double spirals at the leaf base. The rhizome growth habit is variable—most creep along the surface, others are upright. Some have a surface rhizome to which are attached many jointed upright stems that give a shrub-like appearance, while B. philodendroides has an underground rhizome. Propagation is by rhizome cuttings although many can also be grown from leaf cuttings.

Rex Begonias (Rex Cultorum Group): These are sometimes treated as members of a rhizomatous group but are so widely cultivated for their spectacular ornamental foliage that they are generally treated as a separate group. The species B. rex Putz is still in cultivation in America and in collections in Australia. Its obvious hor­ticultural potential was soon realised after its accidental introduction to England in 1856 from Assam, India. Breeding soon began and a vast range of cultivars has arisen as a result of its hybridisation; outstanding Asiatic species include B. annulata, B. decora, B. diadema, B. laciniata, B. robusta and B. xanthina. The group is now generally referred to botanically as the Begonia Rex Cultorum Hybrids.

Plants mostly rhizomatous with inconspicuous white or pink flowers but spectacular leaves patterned with various combinations of green, silver, grey, red, bronze and purple. Propagation is by leaf cuttings.

Trailing or scandent Begonias: A small group of trailing species branching freely from the base and especially from the nodes when in contact with a suitable moist surface; they are popular for hanging baskets and B. glabra is perhaps the best known in Australia. In their native habitat, anchored by roots at each node, they scale trees in search of light, cascade down embankments, or simply spread over large surface areas. Propagation is by stem cuttings.

Tuberous Begonias: This is a large group sometimes subdivided into the tuberous, tuberhybrida, semi-tuberous (maple-leaved), hiemalis (elatior begonias), chiemantha and chiemantha-like (winter-flowering Lorraine or Christmas Begonia) groups. The Non Stop Group has achieved recent popularity as open garden plants. Propagation is from side shoots that are about 5 cm long and have a small basal bud. The semi-tuberous group derived from B. socotrana and a red flowering tuberous begonia through further hybridisation gave rise to the (Elatior) hiemalis group which is represented in Australia by plants introduced from the USA. They are mainly grown in South Australia at Myponga and Toolangi, Victoria, chiefly as annual pot plants in various colours both single and double flowering types of the ‘Aphrodite’ and ‘Schwabenland’ series; they are propagated from stem cuttings.

Semi-tuberous Begonias: Often referred to as Maple Leaf Begonias, the semi-tuberous species are native to South Africa. Unlike the tuberous, the semi-tuberous begonias are semi-dormant during the winter months. New growth ceases, foliage is shed, and some stem dieback may occur. Within two weeks or so new leaves are visible and the plant resumes normal growth. They have an irregular tuber, mostly above the surface, and a main stem that is thick at the base, slowly tapering and freely branching. Stems often develop swollen sections, a form of food and water storage in case of drought. Many previously named species have now been grouped as B. dregei, which is now thought to be a naturally occurring hybrid, as self-pollination of a single variety produces offspring with variable leaf shapes and incisions.

Begonia Tuberhybridas (Hybrid tuberous Begonias): In the 1860s six tuberous begonias were discovered in the Andes of South America and immediately European breeders began experimentation with them. The present-day outcome is a vast hybrid tuberous group with cultivars derived from hybridisation of many species, chiefly B. boliviensis, B. clarkei, B. davisii, B. pearcei and B. veitchii, all from the Andes.

Stems may be absent to about 50 cm tall and erect or pendulous, fleshy and mostly hairy. Flowers mostly 3 in axillary clusters with a single male flower between 2 females, occasionally paired. The flowers are variously coloured, sometimes double, bicoloured, fringed or fragrant; summer. The tubers are concave above. [B. ×tuberhybrida Voss, B. ×tuberosa hort.]

The flower types are generally grouped as follows: Single, Frilled, Crested, Daffodil-flowered, Camellia-flowered (sometimes ruffled), Rosebud, Carnation, Picotee (flowers mostly large and double, in camellia kinds the tepals are edged differently or merged with the same colour), Marginata (margin coloured), Marmorata (white marbled), Pendula (foliage pendulous, widely used in hanging baskets), Multiflora (plants bushy, compact, flowers numerous).

Pendulous cultivars:  Some of these cultivars grown in Australia were raised by Vetterle and Reinelt, California, a nursery active in the 1940s to 1960s. Frank Reinelt was the hybridiser of the Pacific Group of hybrid begonias and the Cascade pendula hybrids.

Source: Wright, P.; Goodwin, J.; Spencer, R. (1997). Begoniaceae. In: Spencer, R.. Horticultural Flora of South-eastern Australia. Volume 2. Flowering plants. Dicotyledons. Part 1. The identification of garden and cultivated plants. University of New South Wales Press.