Cleistocactus strausii
The cactus prefers free draining soils, strong sunlight, but not high temperatures — in fact it can withstand hard frosts down to -10 °C. In its natural habitat it receives plenty of water during the summer, but almost none over the winter. In cultivation, watering too much in winter often leads to root rot.
Disocactus × hybridus
Disocactus" × "hybridus is a hybrid between "Disocactus phyllanthoides" and "Disocactus speciosus". It is perhaps the most commonly grown orchid cactus and seems to survive and flower under most conditions. It has a very complex taxonomic history and has been mistaken for "Disocactus ackermannii" for a long time. The name "Cactus jenkinsonii" McIntosh (1829) might be an older name, but there is no combination under "Disocactus".