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.
Harrisia fragrans
This is an erect or spreading cactus with narrow, long stems which can well exceed one meter in length, at times approaching five meters. It is covered in long, yellow or yellow-tipped spines which may be up to 4 centimeters long. It produces enormous tubular flowers up to 20 centimeters long which are sweet-scented and white to pinkish in color. They bloom at night. The fruit is spherical and red or orange in color, measuring up to 6 centimeters wide. The fruits are a favorite food of local birds, which likely help to disperse the seeds. The cactus has been noted to live at least 19 years, and in general has low fecundity; older, larger plants are more likely to survive, and they have higher fecundity, as well. Small plants may benefit from growing with nurse plants.