Cereus peruvianus, also known as the Peruvian apple cactus or columnar cactus, is a species of cactus native to South America, particularly in the Andean region. It is a large, branching cactus that can grow up to 10 meters tall and 1 meter wide.
The Peruvian apple cactus has a distinctive columnar shape with a series of rib-like ridges running vertically along its surface. Its stems are green when young and turn grayish-brown as they age. The cactus produces large, white, nocturnal flowers that bloom during the summer months. The fruit of the Peruvian apple cactus is oblong or pear-shaped, measuring up to 12 cm in length and is yellow-green when ripe.