The common names of ‘Dutchman’s pipe’ and ‘queen of the night’ are not much less awkward the the Latin name of Epiphyllum oxypetalum, which might be why the Latin name is more common than the common names are. Some know it as ‘white ephiphyllum’ or even more simply as ‘white epi’. It is one of the more popular of the epiphyllums; and it is the most popular with white flowers.
The nocturnal flowers appeal to nocturnal pollinators. What we see simply as luminescent white is actually outfitted with exquisite patterns that are only visible to those who can see ultraviolet light, like nocturnal moths. Bats are as blind as . . . well, bats, but can follow the richly sweet fragrance if they choose to. Sunlight disables fragrance immediately, and causes flowers to close soon after.
In the wild, sprawling primary stems can cascade almost twenty feet. Of course, they are much shorter in home gardens. The more pendulous secondary stems that bloom get about a foot long, and perhaps three inches wide. Flowers bloom in summer, and can be half a foot wide and a foot long. Epiphyllums naturally hang from trees as epiphytes, so will do the same from hanging pots.