T. articulatus is an exemplar of cactus very easy to cultivate because it resists very well to the temperature differences. Its name comes from the Greek and means "ash", in reference to its usual colour tending to greyish, but probably also due to the spontaneous growth of different species on the ashes of the volcanoes. Its stem has a globose shape, tuberculated and with big white and woolly areoles. From these ones come out some flattened thorns, of white colour and that are very long. The flowering period is spring, the beautiful flowers bloom at the top of the plant; they are very delicate with shades ranging from white to yellowish.