First hybrids What's in a name? What do we call them today?
What we commonly call "epiphyllums" today are actually hybrids of epiphytic cacti species native to the jungles of Central and South America, as well as Mexico. The word epiphyllum in Greek means "upon the leaf" and the flowers appear to bloom directly on the leaves. Jungle cacti, however, have no leaves; their leaf-like parts are actually thickened stems or branches. These stems are typically flat but often grow in a triangular shape. Unlike most desert cacti, epiphyllums are not covered with spines. They do, however, have hair bristles or tiny spines in the areolas, some more so than others.
In their native habitat, the epiphytic species often grow in the forks of trees or in rock crevices where their small, fibrous roots take hold in decaying vegetative matter. Some epiphytic species are rooted in the ground and use aerial roots to climb up tree trunks. The plants can draw moisture from the humid air and tropical rains. Because their root systems are relatively small, continually water-soaked soil will suffocate the roots. The jungles' frequent rains are ideal for keeping plant roots moist but not saturated. High in the trees, the plants receive much-needed air circulation from shifting tree branches which also let in the dappled sunlight they need to produce blooms.
It was in these tropical jungles of the New World that European explorers discovered epiphytic cacti. Night-blooming species are mostly white or white with pale yellow overcasts or traces of yellow in back petals. There are, however, a few species that have color in their flowers, notably the orange-red blooms of Nopalxochia ackermanii, the red Heliocereus aurantiacus, the scarlet Heliocereus cinnabarinus and the purplish-red Heliocereus speciosus.
Hybridizing has produced today's day-blooming epis in a variety of colors, sizes and shapes. Blossom size and style range from one inch to 12 or more inches across, single-petaled, multi-petaled, pointed or rounded petals, and every combination thereof. Colors, too, cover a spectrum from pure white to creams and green tinges, pinks and roses in all hues, reds, oranges, deep purples, violets and lavenders, pale yellows to deep gold -- every combination and shading imaginable.
Much time and effort has gone into obtaining some colors. A yellow blossom was not bred until the late 1950s when Southern California hybridizers Paul Fort and Garland O'Barr produced the epiphyllum "Reward", a nine-inch flower with chrome yellow back petals and pale yellow to white inner petals. It was one of three yellow-flowering plants produced from a cross of two white hybrids, one of which had a slight golden cast. The first cutting from "Reward" sold for $400. Today there are a number of beautiful yellow epis; however, a blue one still eludes hybridizers.
Although the plants that the San Diego Epiphyllum Society was formed to promote are called "epiphyllum", the question is "Are they truly Epiphyllums?" There are conflicting opinions on the subject and the issue causes a lot of debate among members around the world. For the casual hobbyist, the ins and outs of the arguments can be confusing; but for now there is no consensus on what name to apply to the epiphytic hybrids the epiphyllum societies promote.
The bottom line is that the true epiphytic Epiphyllum species is just one of many epiphytic species used in hybridizing. In fact, some believe that Epiphyllum was used in as little as ten percent of the initial crosses.
The first epiphytic crosses involved Heliocereus and Nopalxochia. According to author Scott Haselton, the earliest records go back to 1830 in England where Jenkinson and Smith recorded the first hybrids. About 1820, Heliocereus speciosus was introduced to English collectors shortly after Nopalxochia phyllanthoides had been distributed. The ease in crossing these two plants led to many fine hybrids which were named and offered for sale.
Then came the large-flowering, scented Epiphyllum crenatum which was imported into Europe in 1840. From then on, many English, German and French hybridizers began producing epiphytic hybrid crosses.
In 1813 Englishman Adrian H. Haworth first described Epiphyllum phyllanthus and thus established the name Epiphyllum as a valid name for a Genus. However, in 1820, Link, in Germany, described the same plant as Phyllocactus phyllanthus, unaware that Haworth had already described the plant. Since Epiphyllum phyllanthus was the first name published, Epiphyllum became the valid name for this genus and phyllocactus became a synonym for epiphyllum. In fact, phyllocactus became established as a word to describe not only the epiphyllum species, but all epiphytic cacti including the hybrids produced by various epiphytic cacti plants.
There is some belief that American nurserymen in the early 1900's did not like the name "phyllocactus", but preferred "epiphyllum" and either didn't know or didn't care that in Germany "epiphyllum" did not describe all epiphytic cacti and their hybrids. Perhaps they just "assumed" that "epiphyllum" and "phyllocactus" were completely synonymous. When the Epiphyllum Society of America was established in 1940 in Los Angeles, the founding members apparently complied with this thinking. At least, this is theory proposed by some today based on articles from cacti journals and newsletters published at that time.
While most everyone agrees that our hybrid plants aren't all Epiphyllum hybrids, the real discussion today is "What is the most accurate word to call our plants?"
There are many suggestions: epiphyllum (with a lower case "e"), epicactus, phyllocactus, epi, or Epiphyllum Hort. (or even Epiphyllum Hort. non Haworth).
Those who prefer epiphyllum feel that a lower case "e" and not italicized or underlined is acceptable. Since "epi" means "upon" and "phyllum" means "leaf", it makes sense to call these "man-arranged hybrids" epiphyllums because they produce flowers on leaf-like stems.
Others feel that epicactus is best; however, some feel that this would not be completely accurate because epicactus also includes other epiphytic cacti including Schlumbergera and Rhipsalidopsis hybrids.
Epi is what most members call the plants; rarely do you hear society members using the complete "epiphyllum" in conversation. This may be too casual for some.
Epiphyllum Hort. means "Epiphyllum as used by hobbyists" or in other words, hybrids. This is probably the most accurate of all the choices; however, it's a bit awkward for conversation and casual writing.
The term "orchid cactus" is almost completely dismissed as the plants are not related to orchids in any way.
Until there is a consensus among the experts, SDES has elected to continue as it has been. In our publications we will use epiphyllum (lower case "e", no italics) and epi. Although there has been talk among other epi societies about changing their names, at this time SDES will remain the San Diego Epiphyllum Society, Inc.
For a more comprehensive description of epiphytic cacti species, please see Myron Kimnach's article The Species of Epiphytic Cacti in the Epiphyllum Society of America's Directory of Species and Hybrids, Fourth Edition.