It can be cultivated in temperate climates, requiring soils with good drainage and ample moisture in part-shaded or sunny positions.

[3] Anatomically, the individual flower bears a sessile anther (that is, it lacks a filament), which lies next to the stigma at the end of the style.

[1][8] Richard Salisbury had attended the talk and controversially published the species as Hylogyne australis, or southern hylogyne, in Joseph Knight's 1809 book On the cultivation of the plants belonging to the natural order of Proteeae,[9] thus claiming precedence over Brown's formal 1810 description.

[10] James Ross described a new species of waratah, Telopea tasmaniana, in his Hobart Town Almanack in 1835,[2] but it is now considered a synonym of T. truncata.

[1] In 1891, German botanist Otto Kuntze published Revisio generum plantarum, his response to what he perceived as a lack of method in existing nomenclatural practice.

[15] The genus is classified in the subtribe Embothriinae of the Proteaceae, along with the tree waratahs (Alloxylon) from eastern Australia and New Caledonia, and the South American genera Oreocallis and Embothrium.

[16][17] Almost all of these species have red terminal flowers, and hence the subtribe's origin and floral appearance most likely pre-dated the splitting of Gondwana into Australia, Antarctica, and South America over 60 million years ago.

[22] Fossil remains of Telopea truncata have been recovered from early to middle Pleistocene strata at Regatta Point in western Tasmania.

[23] Leaves identical to (and classified as) Telopea truncata have been recovered from early Oligocene deposits around Lake Cethana near Sheffield.

[26] It grows on moist acidic soils in wet sclerophyll forest or subalpine scrub at altitudes of 600 to 1200 m (2000–4000 ft).

[29] The prominent position and striking colour of the flowers of T. truncata and many of its relatives within the subtribe Embothriinae in both Australia and South America strongly suggest it is adapted to pollination by birds, and has been for over 60 million years.

[4] The Tasmanian waratah has a swollen woody base largely under the soil known as a lignotuber, which stores energy and nutrients as a resource for rapid growth after a bushfire.

[31] These are roots with dense clusters of short lateral rootlets that form a mat in the soil just below the leaf litter.

[33] The flowers of the Tasmanian waratah provide ample nectar and hence are a food source for bird visitors to the garden.

[39] Geoffrey Smith observed in 1909 that the collection of the flowers for this purpose had caused the decline of some populations on Mount Wellington.