Many plants, even though truly magnificent, have not yet been ‘discovered’ by home growers and continue to be only permanent fixtures in botanical gardens. This is true of the species and, in fact, the whole genus Bertolonia. To date nine species have been noted growing in the wild in South America, chiefly Brazil and Ecuador, where they are to be found on the forest floor, in the shade of undergrowth, as well as beside streams both in the humus layer ofand on the rotting trunks of fallen forest giants, together with selaginellas and mosses.
The two species generally found in botanical gardens as well as private collections are the B. maculata and B. marmorata, which is also small, barely 10 to 15 cm (4 to 6 in) high, but has a less hairy stem, leaves that are shortly-elliptical rather than shortly-oval and hairy only on the margins. Theare coloured purple. More commonly encountered, however, are the hybrids of the two (for bertolonias interbreed readily), and these exhibit marked diversity. An extremely handsome but rare species is B. pubescens, which has leaves covered with long white hairs and marked with a brown stripe between the midrib and adjoining vein.
Frequently cultivated are hybrids between the genera Bertolonia and Sonerila designated as x Bertonerila. Commonest of these is x Bertonerila houtteana, about 30 cm (1 ft) high with dark green leaves veined purple and coloured purple on the underside.
Bertolonias should be grown in a mixture of peat, sand, rotted wood dust and crushed charcoal or one of the soilless composts. They also do well on rotting pieces of wood covered with sphagnum moss. High atmospheric moisture is a must and for this reason the plant is ideal for growing in demijohns. Propagation is by seeds sown on the surface of the compost.