Cactus That Blooms at Night Once a Year

Selenicereus

• Selenicereus is a cactus genus with a number of night-blooming species. Perhaps the most famous is Selenicereus grandiflorus, also known as queen-of-the-night cactus. This cactus has white, vanilla-scented blossoms that average 8 inches across. Flowers open for only one night, and only for a few hours. Flowers of selenicereus form a tube-like shape that are scaly on the outside. Selenicereus has a creeping growth habit and needs a trellis or other support system.

Hylocereus

• Most of the species in the cactus genus Hylocereus bloom at night. However, most members of the genus are too large to be grown in containers or small yards. The most common species is Hylocereus undatus, a vine-like cactus with very small, unobtrusive spines. The edible fruits of this plant are known as dragon fruit or pitaya. The outer petals of the short-lived flower are green or yellow, while the inner petals are white.

Peniocereus

• Some members of the genus Peniocereus bloom at night, including Peniocereus greggii, or Arizona queen-of-the-night. This tall, thin cactus has a bushy growth habit, although taller specimens can require support. The flowers typically all open on the same night and close during the morning of the following day. Stems can appear black in color, but they are actually dark green. This cactus has an enlarged, tuberous taproot that can weigh 130 pounds or more; most specimens average only 10 to 20 pounds.

Night-Opening Species

• A number of cactus species possess flowers that initially open at night, but which remain open for several days. Most species in the genus Epiphyllum fall into this category. In the wild, Epiphyllum species have white to pink flowers, but commercial hybrids are available in a rich variety of colors. Species in the genus Echinopsis also open initially at night. Depending on the species, blooms remain open during the daytime for one to three days.