Pelargonium species T-Z are found on this wiki page
Pelargonium torulosum is a tuberous species from the Cape Province in South Africa, Klipplaat, and Sutherland where it grows in sandy soil under bushes. Note the small tubers, which spread at ground level. (Section Ligularia). Photos David Victor.
Pelargonium triandrum is a tuberous species from the Cape Province, in South Africa, along the Olifants River from Clanwilliam to Algeria. It grows on sandstone in broken succulent veld or dry fynbos. This species has four petaled flowers, which may be cream to pale yellow, with wine red feathering on the upper two. Note the prominent stamens, presumably for a particular pollinator (see also Pelargonium oblongatum, which is not closely related). It flowers from October to December. The name is derived from the fact that it has only three, very long fertile stamens. (Section Hoarea, punctatum group). Under cultivation conditions this species requires a treatment similar to others in the Hoarea Section. In dry winter conditions it requires additional water to maintain the large leaves in full growth and avoid desiccation or premature dormancy. In bloom, usually in May and June in southern California, it provides a striking, delicate appearance in bloom. The first three photos from David Victor. The last photo from Andrew Wilson.
Pelargonium trifoliolatum is a tuberous species from the Southwestern Cape of South Africa, on the western escarpment, from Piketberg to Groot Drakenstein. It grows on clay soils in renosterveld and sand in fynbos. Flowers can be cream, yellow or pink, with wine red blotches on the "knees" of the petals. It flowers from October to January. The name refers to the incision of the leaves. (Section Hoarea, Heterophyllum Group). Photos David Victor.
Pelargonium triste is a geophyte with a large subterranean tuber and tuberous roots with carrot like leaves and flowers that are dull yellowish green to brownish purple edged with a lighter margin. It grows in sandy flats and lower slopes over a broad region of the Cape Province and also can be found in bloom over a long period. The first pictures were taken by Mary Sue Ittner in Namaqualand August 2001 and a third photo by Bob Rutemoeller was taken near Tulbagh August 2006. The last photo was taken by Cameron McMaster September 2011 near Darling.
Pelargonium undulatum is a tuberous species from the Southewestern Cape area of South Africa, in the vicinity of Worcester, Karoo Poort, the Hex River Valley and further East. It grows in sandy soil or on shale in low karroid vegetation. Flowers are white, cream, yellow or pale pink, the upper two having a wine red blotch and the lower three a wine red stripe down the centre. The petal edge is undulate, giving the plant its name. It flowers from September to October. (Section Hoarea, Attenuatum Group). Photos David Victor.
Pelargonium vinaceum is a tuberous species from Southern Namibia, Rosh Pinah, in the Richtersveld to South of Steinkopf, in South Africa. It grows in karroid vegetation in granites, shale or sand. Flowers may be cream to pale yellow, with wine red blotches in the centre of the upper two. It flowers from October to November. (Section Hoarea, Incrassatum Group). Photos David Victor.
Pelargonium violiflorum is a tuberous species from the Southwestern Cape of South Africa, around Ashton, Robertson and Bonnievale. It grows on shale or sandstone in mountain renosterveld or karroid shrubland. Flowers are white. Flowering takes place during September and October. The name refers to the flowers looking like English violets. (Section Hoarea, Pinnatum Group). Photos David Victor.