Saturday, March 1, 2008

1. What is an epiphyllum?

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.

2. First hybrids

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

3. What's in a name?

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.

4. What are they called today?

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.

5. Planting and growing instructions

Propagation of unrooted cuttings
  • Normaly you get your cuttings unrooted, although some nurseries sell the cuttings rooted. The advantage of the latter is that the plant will flower one year earlier, but rooted cuttings are more expensive. The unrooted cuttings should be about 12 - 20 cm in length, but shorter will do. When receiving the cuttings, leave them in a sheltered and cool place for one to two weeks to make a callous, thereby preventing rot when planted. Some growers dip the cutting in a "Rootone" to enhance the developing of roots. I have however never used it myself. You may use clay pots or plastic pots. If you have a tendency to over water, then use clay pots, if not, use plastic pots.
  • Put one third of the cutting down in the mix and tie it loosely to a stick for support. Keep the mix slightly damp and keep the cuttings in a shaded place for 6 to 8 weeks. At that time they ought to have produced roots. Sometime you will see roots develop on the top of the cuttings. It is a sign that roots have also developed under ground.
  • See Fig. 1 for 3 examples of different well-developed cuttings for planting. The fourts cutting at the right is a typical thin winter shoot, which should be removed as soon as it has been found, as it will never be able to bear good flower buds.

Fig. 1

Potting mixture
  • I have found that a commercial potting mixture, sold in nurseries is quite satisfactory for growing Epiphyllums. The potting mixture has however to be loose in structure, so you might ad some sand, perlite or bark. To make the soil even better you could add 30% oak leaf moil, 20% of ground bark, perlite or grit to 50% houseplant potting soil. Be sure that the mix is coarse and draining the water fast.

Watering and fertilizing
  • Your Epiphyllums must never dry out. On the other hand they must never be soggy. Water them as you usually water indoor plants, until the water flows through the drain holes, and remove the extra water in the saucer. Epiphyllum prefer soft water, so if possible, use rain water.
  • After a long winter, where the plants only need to be kept moist, you may increase the watering from March on. Use your fingertip to feel if the plants need water. If the soil is wet and cold, wait some days with further watering. How frequently you water your plants depents on the light, the day and night temperature and the size of the plant. Water regulary, until the middle of October, where the new branches should be fully mature. From that time on gradually reduce the amount of watering.
  • Normally I add a commercial liquid fertilizer i.e. 5-1-4 every time I water from early spring to fall. I do not fertilize in the winter.

Light requirements
  • Epiphyllums in nature grow on the branches of trees often in rain forests, and their roots take hold in the decaying vegetable material collected on the branches. Thus they grow in filtered sunlight. If you grow them indoors, they prefer a window with morning or afternoon sun. If you have a garden, they will do fine outdoors in a shaded place. The will not tolerate full sunshine.

Temperature and himidity
  • Epiphyllums are very sturdy. They can tolerate temperatures up to 30°C, but prefer high humidity, between 50% and 80%, although lower may do it. In my winter garden the humidity is between 40% and 80%.
  • To get Epiphyllums to flower in the spring, it is essentiel to keep them at low temperature in the winter during the nights and to avoid artificial light exposure after sundown. They have to be kept at a night temperature not above 14°C, and best around 10°C. With higher temperatures they will not develop flower buds. They can tolerate temperatures down to 8°C.

Care of your Epiphyllums
  • Besides taking care of the mix, the humidity, the light, the fertilizer and the temperature, you also have to check the plants for unwanted leaves. All year around the Epiphyllums have a tendency to sprout new leaves in all directions. During winter the leaves that develop are thin and soft without strength, (Fig. 1) remove them all. Shoots may develop year around from the top of the plants or from the areoles of the leaves where the flowers should come. Fig. 2. I remove them, because I do not want, especially the vigorous plants, to grow to huge. When the plants grow, you might direct the leaves growth by tying them to a bamboo stick, or similar for support. Keep the plants as slim as possible or it will soon grow like crazy Fig 3, 4, 5 and 6. The only new leaves you should keep are the leaves that grow out from the bottom of the plant. Fig. 7 and 8. However, no rules without exceptions. The Epiphyllum called Deutsche Kaiserin has a hanging growth, with a lot of flower buds from the hanging leaves. It is therefore best grown in a hanging basket.

Fig. 2

Fig. 3

Fig. 4

Fig. 5

Fig. 6

Fig. 7

Fig. 8

  • Normaly, pruning or cutting back should not be necessary. However, if you have to remove a stem because it is damaged or too old for flowering always do it from the base of the plant otherwise the plant will produce new shoots near the cut and this will ruin the appearance of the plant. Old leaves, where all the areoles has been used, will never flower again, and migth be removed. However, they may be used as new cuttings.

  • Your Epiphyllum will bloom after 1 to 4 years. Some will take longer. The blooming season is from April to July, depending of the type of the plant and the day temperature the Epiphyllum has been growing at during the winter. When buds are seen, don't turn the plant around, as this migh cause the buds to drop. Fig 9. Wait until the buds are so big, that they are nearly opening. Now you can move them indoors if you like, or to another place. Bud drops might also happen naturally if the plant produces more buds than it can reasonable handle. Sometimes new leaves are developing together with buds, remove these shoots. Fig. 10. The flowers will last from one night to several days.

Fig. 9

Fig. 10
  • I have observed, that Epiphyllums, who has been grown indoors on a windowsill, will bloom a little earlier than Epiphyllums, which had been grown in the winter garden, where the day temperature is somewhat lower. The American species are sometimes blooming during summer or early autum.

  • When the plants have developed three or four new branches it might be time to repot them. Also, when the plant tends to fall over when you move it around, it might be time for repotting. Use fresh mix, and don't remove to much of the old one. Do not water the first week after repotting. Normaly it is not necessary to repot them more frequently than every 3 to 4 years. The best time to do the repotting is after the end of blooming.

  • Epiphyllums are very robust. They might however, be attacked by scale insects and mealy bugs. Remove them with a commercial product, found in nurseries. If you have the plants outdoors during the summer, you should place them above the ground i.e. on a bench or a shelf, as snails and other gnawing insects can damage them. Please be aware of groups, as they can rip the leaves in a very short space of time.