This section is from the book "Handbook Of Hardy Trees, Shrubs, And Herbaceous Plants", by W. Botting Hemsley. Also available from Amazon: Handbook of hardy trees, shrubs, and herbaceous plants.
This order comprises one vast genus, Begonia, containing upwards of 350 species, and one or two monotypic genera. The species are mostly succulent herbs of variable habit and duration, and many have perennial tuberous rhizomes. Leaves alternate, simple, variously lobed or entire. Flowers often very showy, white, rose, scarlet or yellow, unisexual and unsymmetrical. Segments of the perianth 2 or more, all petaloid. Stamens many; filaments free or connate. Fruit capsular or baccate, often angular and 3-winged. Seeds numerous, very minute. Nearly all the species are tropical, but one or two from the Andes have recently been introduced and distributed as hardy plants, and one Chinese species needs only slight protection. Many others may be planted out in Summer in sheltered situations.
1. B. Evansiana, syn. B. discolor. - This is a very free-flowering large-leaved caulescent species from China. The leaves unequally cordate, sharply toothed, hispid above, and bright red on the veins beneath. Flowers in terminal panicles, rosy-pink.
2. B. Veitchii. - A very fine species, found at an elevation of 12,000 feet in Peru, Stemless, with thick fleshy oblique cordate lobed leaves and very large vermilion-coloured flowers, about two on each scape, with rose-coloured bracts.