Selenicereus grandiflorus aka Night Blooming Cereus

Selenicereus grandiflorus is a cactus called queen of the night. People also call it vanilla cactus or night-blooming cereus. It belongs to Cactaceae, the cactus family. Kew gives its native range as Mexico to Guatemala. In Mexico, it grows from Tamaulipas to Tabasco. Its native range also takes in the northern Caribbean. Kew places it in tropical lands with dry seasons. It is not native to Britain or Ireland.

This cactus stays green all year. It climbs or sprawls; it does not form a tree. Useful Tropical Plants gives a height of 13 feet [4 metres]. Its stems can reach several metres in length. They bear spines and are green or blue-green. Each stem is about 0.08 feet [0.025 metres] across. The stems grow many aerial roots, or roots above ground. Kew calls it an epiphyte: it grows on other plants. Long stems and a climbing habit give it its shape. The supplied sources give no spread for this species in gardens.

The flowers have a scent and open at night. These traits help explain some of the plant's common names. The evidence for this species gives no bloom season. It gives no firm flower size or colour, either. The fruit is shaped like an egg. It is about 0.26 feet [0.08 metres] long. Useful Tropical Plants says people can eat the fruit. People gather wild plants for food and medicine. Growers raise it for its looks, too. The flowers that open at night add to its garden appeal.

In the tropics, wild plants grow in a range of places. They grow in dry forests, and forests that shed some leaves. They also grow in flooded forests and on coastal dunes. Some grow among scrub on bare limestone in full sun. Records range from sea level to about 4,265 feet [1,300 metres]. These records do not show how often to water garden plants. The supplied species pages give no hardiness zone or winter limit. They name no pests or diseases for this species.

Useful Tropical Plants reports that people use flowers and stems as medicine. Uses include heart problems, fluid retention, and rheumatism. It also reports that growers raise plants for compounds that act like digitalis. The source lists no known hazards. This does not mean it is safe for pets. It cites a 2013 IUCN review, which ranks it as Least Concern. The account says it grows across a wide area. It lists no major known threats. Groups of these plants grow in several protected areas.