Trichocereus macrogonus var. pachanoi, commonly known as San Pedro cactus, is a fast-growing columnar cactus native to the Andean mountain deserts, specifically found in the high-altitude regions of Ecuador, Peru, and Colombia, between 6,600 to 9,800 feet. This cactus typically reaches a height of 10 to 20 feet with a diameter of 6 to 15 inches. It features light to dark green stems with 6 to 8 ribs and is adorned with areoles from which spines emerge. The San Pedro cactus is renowned for its large, fragrant white flowers that bloom at night, usually in late spring to early summer, and are quite showy, attracting nocturnal pollinators.

The San Pedro cactus is valued for its ease of growth and low maintenance requirements, as well as its striking appearance and night-blooming flowers. It is commonly used as an ornamental plant in xeriscapes, rock gardens, and as a potted specimen in areas where it cannot survive outdoors year-round. It thrives in well-draining soil, requires little water once established, and prefers full sun to partial shade. While it is generally disease-resistant, overwatering can lead to root rot. It is important to note that the San Pedro cactus contains mescaline, a psychoactive compound, and therefore it has legal restrictions in some areas due to its potential for misuse.CC BY-SA 4.0