Native to Brazil and Argentina

Watering: Needs moderate to copious waterings in the summer (it is more demanding than other cactus), but do not overwater, keep dry in winter at a minimum temperature of 0°C.

Hardiness: It is quite frost resistant if kept dry.

Exposition: The plant tolerates bright situations which encourages flowering and heavy spine production but is likely to suffer from sun scorch or stunted growth if over exposed to direct sunlight during the hottest part of the day in summer. It grows well with filtered sunlight or afternoon shade..

Source: Planet Desert

Scientific classification

Kingdom: Plantae
(unranked): Angiosperms
(unranked): Eudicots
(unranked): Core eudicots
Order: Caryophyllales
Family: Cactaceae
Subfamily: Cactoideae
Tribe: Trichocereeae
Genus: Rebutia

                         – Wikipedia.