Epiphyllum oxypetalum

Queen of the Night is a night-blooming, tropical epiphyte to lithophyte, an organism that grows on the surface of another plant and derives its moisture and nutrients from rain, the air and debris collecting on the organism.  This member of the cactus family is the most cultivated species in the genus.  It has huge, showy, very fragrant white flowers that open only once, at night and are typically only last that one night.  If pollinated, the flowers are followed by 5" long, oblong, purple/red fruits.

This cactus grows in a rainforest setting rather than a hot dry location so will need more water than most cacti. In its native habitat, it is usually found growing on trees, but it can easily be grown in a pot. There are no true leaves, but flattened stems that can be easily rooted. A mature plant can produce flowers from spring through mid-summer.

Give this plant a well-drained average succulent/cactus soil mix in partial shade or bright, indirect light. Soak the soil completely when watering and water frequently, letting the top of the soil dry out between watering. Bring inside when temperatures cool to mid 30s and cut down on watering during the winter to 1-2 times per month.

It can be grown as an outdoor tropical plant in zones 10 and 11.  In cooler zones it can be placed outdoors during the summer months, then brought in as the temperatures drop.  

Growing up to 10' tall and 3' wide, when growing in a container, ensure that the plant remains stable in its container.  Should it become top-heavy, trimming the long stems back can serve as a solution as well as repotting into a larger or heavier container.  

Insects, Diseases, and Other Plant Problems:  No significant problems

VIDEO Created by Laura Barth for "Houseplants, Succulents, and Cacti", a plant identification course offered in partnership with Longwood Gardens.