Schlumbergera
Encyclopedia
Schlumbergera is a genus
of cactus
from the coastal mountains of south-eastern Brazil
. Plants grow on trees or rocks in habitats which are generally shady with high humidity and can be quite different in appearance from their desert
-dwelling cousins. Most species of Schlumbergera have stems which resemble leaf-like pads joined one to the other and flowers which appear from areole
s at the joints and tips of the stems. Two species have cylindrical stems more similar to other cacti. In Brazil, the genus is referred to as (May flower), reflecting the period in which they flower in the Southern Hemisphere.
This genus contains the popular house plants known by a variety of names including Christmas Cactus, Thanksgiving Cactus, Crab Cactus and Holiday Cactus, which are Schlumbergera cultivar
s, and flower in white, pink, yellow, orange, red or purple. (The Easter Cactus or Whitsun Cactus, which may also be called a Holiday Cactus and has vivid scarlet flowers in the most commonly grown form, is now placed in the genus Hatiora
.) The cultivars of Schlumbergera fall into two main groups:
) or on rocks (epilithic
) and can form sizeable shrubs with woody bases. They are leafless, the green stems acting as photosynthetic
organs. The stems are composed of segments, which take one of two forms. In most species the segments are strongly flattened (cladodes) being made up of a central core with two (or more rarely three) "wings". Special structures characteristic of cacti, called "areole
s", then occur at the ends of the segments of the stem. In two species the stems are less flattened, more cylinder-shaped, and the areoles are arranged in a more or less spiral pattern all over the segments. In both cases, the areoles, which may have wool and bristles, are where the flower buds appear.
The flowers either hang downwards and are almost regular (radially symmetrical or actinomorphic) or, as in most species, are held more or less horizontally with the higher side of the flower different from the lower side (radially asymmetrical or zygomorphic). In those species whose flowers are held up, their angle with the horizontal is relatively constant and is characteristic of the species. Each flower has 20–30 tepal
s. The outer tepals – those closer to the base of the flower – are short and unconnected, and spread out or curve backwards. The inner tepals – those towards the tip of the flower – are longer and become progressively more fused together at the base to form a floral tube. In some species the difference between the outer and inner tepals creates the appearance of a "flower within a flower". The flowers produce nectar in a chamber at the base of the floral tube.
The many stamen
s are arranged in two series, which is a distinctive characteristic of the genus. The inner stamens are fused at the base to form a short tubular structure. The outer stamens arise from along the floral tube. The style is usually dark red and has a stigma
with 6–8 lobes; the style plus stigma is roughly the same length as the stamens. If the flower is fertilized, a fleshy fruit
forms, either smooth or with ribs. The brown or black seed
s are about 1 mm in diameter.
The taxonomic history of the genus is complicated; it has been detailed by McMillan and Horobin. The modern genus Schlumbergera was created by Charles Lemaire
in 1858. The name commemorates Frédéric Schlumberger, who had a collection of cacti at his chateau near Rouen
. Lemaire placed only one species in his new genus – a plant discovered in Brazil in 1837 which had been named Epiphyllum russellianum by William J. Hooker. Lemaire re-named it Schlumbergera epiphylloides (under the current rules of botanical nomenclature
it should have been called Schlumbergera russelliana, which is its current name).
Lemaire noted the similarity of his Schlumbergera epiphylloides to a species first described as Epiphyllum truncatum by Adrian Hardy Haworth
in 1819, but did not accept that the two species should be included in the same genus. In 1890, Karl Moritz Schumann
created the new genus Zygocactus, transferring Epiphyllum truncatum to Zygocactus truncatus. Although he later placed it back in Epiphyllum, abandoning Zygocactus, the generic name Zygocactus continued to be widely used.
In 1913, Nathaniel Britton
and Joseph Rose
followed Lemaire in keeping Schlumbergera russelliana and Zygocactus truncatus in separate genera. (They also transferred the Easter Cactus – now Hatiora gaertneri – to Schlumbergera as S. gaertneri, initiating a lasting confusion between these two genera.)
In 1953, Reid Venable Moran
placed both Schlumbergera russelliana and Zygocactus truncatus in the genus Schlumbergera. Other species were added later by David Hunt
, including those formerly placed in Epiphyllanthus, to form the modern total of six full species and a number of hybrids.
The case of Epiphyllum is complex. In 1753 Carl Linnaeus created the genus Cactus. As more species were discovered this proved too broad, and new genera were set up to subdivide the cacti. The genus Epiphyllum was created in 1812 by Haworth, based on Linnaeus's Cactus phyllanthus. In 1831 Johann Link
created the genus Phyllocactus based on the same species. Following Ludwig Pfeiffer
in 1837, the European tradition was to use Phyllocactus for epiphytic cacti with large regular flowers and Epiphyllum for the irregular-flowered species now called Schlumbergera truncata. Under modern rules, Phyllocactus is an illegitimate name, as is Epiphyllum in the sense of Pfeiffer; thus Epiphyllum Pfeiff. is a synonym of Schlumbergera. The true genus Epiphyllum
Haw. now has around 19 species.
s) are given in the list below.
Four hybrids have been named, all made in cultivation (although the first may possibly occur in the wild). The International Code of Nomenclature for Cultivated Plants
recommends that cultivated plants should be named under its rules, not those appropriate for natural species and hybrids. The Group names given below were provided by McMillan and Horobin.
, in the states of São Paulo
, Rio de Janeiro
, Minas Gerais
and Espírito Santo
. Sites where it has been found range from close to the Tropic of Capricorn
northwards to 20°S
, i.e. in the southernmost part of the tropics. Plants grow at altitudes from 700 metres (2,296.6 ft) in the case of S. truncata to 2780 metres (9,120.7 ft) in the case of S. microsphaerica, in either the coastal moist forests
or rocky areas. The natural distribution of Schlumbergera species has become confused because European cultivars were deliberately introduced into some areas, including the Parque Nacional da Serra dos Órgãos, by the Brazilian Agricultural Department, to compensate for over-collecting of wild plants.
Because of their height and proximity to the Atlantic Ocean, the coastal mountains produce high altitude moist forests – warm moist air is forced upwards into higher, colder locations where it condenses. Schlumbergera species grow in habitats which are generally relatively cool, shaded and of high humidity. David Hunt describes collecting specimens in conditions of cloud, drizzle and overnight temperatures down to -4 °C. Plants are epiphytic or lithophytic, growing on moss-covered tree branches or in rock crevices, often in small pockets of substrate formed from decayed leaves and other vegetation. S. microsphaerica is found at higher altitudes, above 2200 metres (7,217.8 ft), in barren rocky habitats, and tolerates higher light levels.
The flowers of Schlumbergera have adaptations for pollination by hummingbird
s: tubular flowers with abundant nectar, and colours towards the red end of the spectrum. Most species require cross-pollination
to set seed. The exceptions are S. kautskyi and S. microsphaerica; as noted above, the latter is found at higher altitudes where humming birds may be absent or less common.
The fruits of Schlumbergera do not open spontaneously when ripe, and appear to be adapted for distribution by birds, which eat the seeds and pulp contained in the fruit. Birds have been observed removing seeds which had stuck to their beaks by rubbing them on tree branches, where the seeds might be able to germinate. Segments may also break off from the stems and take root, thus enabling plants to propagate vegetatively.
s (cultivated varieties) were available in a range of colours and habits, and were used as ornamental plants in "stoves" (heated greenhouse
s) and in houses, where they were popular for their autumn and winter flowering. Many cultivars were selected seedlings of S. truncata, but at least three S. × buckleyi hybrids were available, of which one, now called S. 'Buckleyi', is thought to be the original Christmas Cactus. By the early part of the 20th century, the genus had become less popular, and many of the early cultivars were lost.
From around the 1950s onwards, breeding resumed in Europe, North America, Australia and New Zealand. New plants were produced by crossing among the species and existing cultivars of S. truncata, S. russelliana and the hybrid S. × buckleyi. Treatments which induced mutation
s were also used. The result was a wide range of flower colours which had not been available before, including the first true yellow to be sold commercially, S. 'Gold Charm' (which was a sterile triploid). Breeders aimed for plants which grew strongly, were upright at the point of sale rather than pendulous, had many flowers or buds, and were adapted to living as house plants.
In the 1980s the species S. orssichiana was also used in crosses. The hybrid of S. truncata and S. orssichiana has been named S. × reginae or S. Reginae Group; one of the first cultivars was S. 'Bristol Queen'. S. opuntioides crosses have also been made, but have not resulted in commercially available cultivars.
Attempts have also been made to classify cultivars by colour. A difficulty is that the flowers of many cultivars exhibit different colours depending on the temperature during bud formation and growth. In particular, temperatures below 14 °C (57.2 °F) produce pink tones in otherwise white and yellow cultivars, and strengthen the colour in pink and red cultivars. The availability of iron to the plant has also been suggested to affect flower colour.
In the United States, cultivars are propagated in large numbers for sale before Thanksgiving Day
(the fourth Thursday in November). In Europe, plants are mainly sold later in the year, in the period before Christmas
. A single Dutch grower (de Vries of Aalsmeer
, Holland) was reported in 1989 as producing 2,000,000 plants per year.
The Easter Cactus or Whitsun Cactus is now placed in the genus Hatiora
, but was at one time included in Schlumbergera (or one of its synonyms). The name "Holiday Cactus" has been used to include both Schlumbergera and Hatiora cultivars.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of cactus
Cactus
A cactus is a member of the plant family Cactaceae. Their distinctive appearance is a result of adaptations to conserve water in dry and/or hot environments. In most species, the stem has evolved to become photosynthetic and succulent, while the leaves have evolved into spines...
from the coastal mountains of south-eastern Brazil
Brazil
Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...
. Plants grow on trees or rocks in habitats which are generally shady with high humidity and can be quite different in appearance from their desert
Desert
A desert is a landscape or region that receives an extremely low amount of precipitation, less than enough to support growth of most plants. Most deserts have an average annual precipitation of less than...
-dwelling cousins. Most species of Schlumbergera have stems which resemble leaf-like pads joined one to the other and flowers which appear from areole
Areole
Areoles are an important diagnostic feature of cacti, and identify them as a family distinct from other succulent plants. The areoles on cacti are clearly visible; they generally appear as small light- to dark-colored bumps, out of which grow clusters of spines...
s at the joints and tips of the stems. Two species have cylindrical stems more similar to other cacti. In Brazil, the genus is referred to as (May flower), reflecting the period in which they flower in the Southern Hemisphere.
This genus contains the popular house plants known by a variety of names including Christmas Cactus, Thanksgiving Cactus, Crab Cactus and Holiday Cactus, which are Schlumbergera cultivar
Cultivar
A cultivar'Cultivar has two meanings as explained under Formal definition. When used in reference to a taxon, the word does not apply to an individual plant but to all those plants sharing the unique characteristics that define the cultivar. is a plant or group of plants selected for desirable...
s, and flower in white, pink, yellow, orange, red or purple. (The Easter Cactus or Whitsun Cactus, which may also be called a Holiday Cactus and has vivid scarlet flowers in the most commonly grown form, is now placed in the genus Hatiora
Hatiora
Hatiora Britton & Rose is a small genus of epiphytic cacti which belongs to the tribe Rhipsalideae within the subfamily Cactoideae of the Cactaceae...
.) The cultivars of Schlumbergera fall into two main groups:
- The Truncata Group contains all cultivars with features derived mainly from the species S. truncataSchlumbergera truncataSchlumbergera truncata is a species of plant in the Cactaceae family. It is endemic to a small area of the coastal mountains of south-eastern Brazil where its natural habitats are subtropical or tropical moist forests...
: stem segments with pointed teeth; flowers held more or less horizontally, usually above the horizontal, whose upper side is differently shaped from the lower side (zygomorphic); and pollen which is yellow. They generally flower earlier than members of the Buckleyi Group and although common names are not applied consistently may be distinguished as Thanksgiving Cactus, Crab Cactus or Claw Cactus. - The Buckleyi Group contains all cultivars with at least some features clearly showing inheritance from S. russellianaSchlumbergera russellianaSchlumbergera russelliana is a species of plant in the Cactaceae family. It is endemic to a small area of the coastal mountains of south-eastern Brazil where its natural habitat is moist forest. It grows on trees as an epiphyte...
: stem segments with rounded, more symmetical teeth; more or less symmetrical (regular) flowers which hang down, below the horizontal; and pollen which is pink. They generally flower later than members of the Truncata Group and are more likely to be called Christmas Cactus.
Description
In the wild, the species of Schlumbergera grow either on trees (epiphyticEpiphyte
An epiphyte is a plant that grows upon another plant non-parasitically or sometimes upon some other object , derives its moisture and nutrients from the air and rain and sometimes from debris accumulating around it, and is found in the temperate zone and in the...
) or on rocks (epilithic
Lithophyte
Lithophytes are a type of plant that grows in or on rocks. Lithophytes feed off moss, nutrients in rain water, litter, and even their own dead tissue....
) and can form sizeable shrubs with woody bases. They are leafless, the green stems acting as photosynthetic
Photosynthesis
Photosynthesis is a chemical process that converts carbon dioxide into organic compounds, especially sugars, using the energy from sunlight. Photosynthesis occurs in plants, algae, and many species of bacteria, but not in archaea. Photosynthetic organisms are called photoautotrophs, since they can...
organs. The stems are composed of segments, which take one of two forms. In most species the segments are strongly flattened (cladodes) being made up of a central core with two (or more rarely three) "wings". Special structures characteristic of cacti, called "areole
Areole
Areoles are an important diagnostic feature of cacti, and identify them as a family distinct from other succulent plants. The areoles on cacti are clearly visible; they generally appear as small light- to dark-colored bumps, out of which grow clusters of spines...
s", then occur at the ends of the segments of the stem. In two species the stems are less flattened, more cylinder-shaped, and the areoles are arranged in a more or less spiral pattern all over the segments. In both cases, the areoles, which may have wool and bristles, are where the flower buds appear.
The flowers either hang downwards and are almost regular (radially symmetrical or actinomorphic) or, as in most species, are held more or less horizontally with the higher side of the flower different from the lower side (radially asymmetrical or zygomorphic). In those species whose flowers are held up, their angle with the horizontal is relatively constant and is characteristic of the species. Each flower has 20–30 tepal
Tepal
Tepals are elements of the perianth, or outer part of a flower, which include the petals or sepals. The term tepal is more often applied specifically when all segments of the perianth are of similar shape and color, or undifferentiated, which is called perigone...
s. The outer tepals – those closer to the base of the flower – are short and unconnected, and spread out or curve backwards. The inner tepals – those towards the tip of the flower – are longer and become progressively more fused together at the base to form a floral tube. In some species the difference between the outer and inner tepals creates the appearance of a "flower within a flower". The flowers produce nectar in a chamber at the base of the floral tube.
The many stamen
Stamen
The stamen is the pollen producing reproductive organ of a flower...
s are arranged in two series, which is a distinctive characteristic of the genus. The inner stamens are fused at the base to form a short tubular structure. The outer stamens arise from along the floral tube. The style is usually dark red and has a stigma
Stigma (botany)
The stigma is the receptive tip of a carpel, or of several fused carpels, in the gynoecium of a flower. The stigma receives pollen at pollination and it is on the stigma that the pollen grain germinates. The stigma is adapted to catch and trap pollen with various hairs, flaps, or sculpturings...
with 6–8 lobes; the style plus stigma is roughly the same length as the stamens. If the flower is fertilized, a fleshy fruit
Fruit
In broad terms, a fruit is a structure of a plant that contains its seeds.The term has different meanings dependent on context. In non-technical usage, such as food preparation, fruit normally means the fleshy seed-associated structures of certain plants that are sweet and edible in the raw state,...
forms, either smooth or with ribs. The brown or black seed
Seed
A seed is a small embryonic plant enclosed in a covering called the seed coat, usually with some stored food. It is the product of the ripened ovule of gymnosperm and angiosperm plants which occurs after fertilization and some growth within the mother plant...
s are about 1 mm in diameter.
Taxonomy
The taxonomic history of the genus is complicated; it has been detailed by McMillan and Horobin. The modern genus Schlumbergera was created by Charles Lemaire
Charles Antoine Lemaire
Charles Antoine Lemaire , was a French botanist and botanical author, noted for his publications on Cactaceae....
in 1858. The name commemorates Frédéric Schlumberger, who had a collection of cacti at his chateau near Rouen
Rouen
Rouen , in northern France on the River Seine, is the capital of the Haute-Normandie region and the historic capital city of Normandy. Once one of the largest and most prosperous cities of medieval Europe , it was the seat of the Exchequer of Normandy in the Middle Ages...
. Lemaire placed only one species in his new genus – a plant discovered in Brazil in 1837 which had been named Epiphyllum russellianum by William J. Hooker. Lemaire re-named it Schlumbergera epiphylloides (under the current rules of botanical nomenclature
International Code of Nomenclature for algae, fungi, and plants
The International Code of Nomenclature for algae, fungi, and plants is the set of rules and recommendations dealing with the formal botanical names that are given to plants, fungi and a few other groups of organisms, all those "traditionally treated as plants"., Preamble, para...
it should have been called Schlumbergera russelliana, which is its current name).
Lemaire noted the similarity of his Schlumbergera epiphylloides to a species first described as Epiphyllum truncatum by Adrian Hardy Haworth
Adrian Hardy Haworth
Adrian Hardy Haworth was an English entomologist, botanist and carcinologist.He was the son of Benjamin Haworth of Haworth Hall...
in 1819, but did not accept that the two species should be included in the same genus. In 1890, Karl Moritz Schumann
Karl Moritz Schumann
Karl Moritz Schumann was a German botanist.Dr. Schumann was the curator of the Botanisches Museumin Berlin-Dahlem from 1880 until 1894...
created the new genus Zygocactus, transferring Epiphyllum truncatum to Zygocactus truncatus. Although he later placed it back in Epiphyllum, abandoning Zygocactus, the generic name Zygocactus continued to be widely used.
In 1913, Nathaniel Britton
Nathaniel Lord Britton
Nathaniel Lord Britton was an American botanist and taxonomist who founded the New York Botanical Garden in the Bronx, New York. Britton was born in New Dorp in Staten Island, New York...
and Joseph Rose
Joseph Nelson Rose
Joseph Nelson Rose was an American botanist. He was born in Union County, Indiana. His father died serving during the Civil War when Joseph Rose was a young boy. He later graduated from high school in Liberty, Indiana....
followed Lemaire in keeping Schlumbergera russelliana and Zygocactus truncatus in separate genera. (They also transferred the Easter Cactus – now Hatiora gaertneri – to Schlumbergera as S. gaertneri, initiating a lasting confusion between these two genera.)
In 1953, Reid Venable Moran
Reid Venable Moran
Reid Venable Moran was an American botanist and museum curator. He was curator at the San Diego Museum of Natural History.-References:...
placed both Schlumbergera russelliana and Zygocactus truncatus in the genus Schlumbergera. Other species were added later by David Hunt
David Hunt (botanist)
David Richard Hunt is an English botanist and taxonomist. He is a specialist in cacti and notably compiled the 1999 CITES Cactaceae Checklist.- References :...
, including those formerly placed in Epiphyllanthus, to form the modern total of six full species and a number of hybrids.
Synonymy
The following genera are now synonyms of Schlumbergera (i.e. they have no species not moved into Schlumbergera):- Epiphyllanthus A.BergerAlwin BergerAlwin Berger was a German botanist best known for his contribution to the nomenclature of succulent plants, particularly agaves and cacti. Born in Germany he worked at the botanical gardens in Dresden and Frankfurt...
- Opuntiopsis KnebelGottfried KnebelGottfried Knebel was a German botanist. He was the author of the cactus genus Opuntiopsis, an invalid name according to the current rules of botanical nomenclature; it is now a synonym of Schlumbergera. The species Mammillaria knebeliana Boedeker is said to have been named in his honour.-...
(nom. inval.) - Zygocactus K.Schum.Karl Moritz SchumannKarl Moritz Schumann was a German botanist.Dr. Schumann was the curator of the Botanisches Museumin Berlin-Dahlem from 1880 until 1894...
- Zygocereus FričAlberto Vojtech FricAlberto Vojtěch Frič was a famous Czech botanist, ethnographer, writer and explorer. He undertook 8 voyages to America, discovered, described and catalogued many species of cactus....
& Kreuz.Kurt KreuzingerKurt Kreuzinger was a German botanist, best known for his work with Cacti.According to IPNI , he died in 1989 .- References :...
(orth. var.) - Epiphyllum Pfeiff.Ludwig Karl Georg PfeifferLudwig Karl Georg Pfeiffer, also known as Louis Pfeiffer was a German physician, botanist and conchologist.-Biography:He received his education in Kassel, and became professor of pathology there in 1828...
but not Epiphyllum Haw.Adrian Hardy HaworthAdrian Hardy Haworth was an English entomologist, botanist and carcinologist.He was the son of Benjamin Haworth of Haworth Hall...
The case of Epiphyllum is complex. In 1753 Carl Linnaeus created the genus Cactus. As more species were discovered this proved too broad, and new genera were set up to subdivide the cacti. The genus Epiphyllum was created in 1812 by Haworth, based on Linnaeus's Cactus phyllanthus. In 1831 Johann Link
Johann Heinrich Friedrich Link
Johann Heinrich Friedrich Link was a German naturalist and botanist.Link was born at Hildesheim as a son of the minister August Heinrich Link , who taught him the love for nature through collection of 'natural objects'...
created the genus Phyllocactus based on the same species. Following Ludwig Pfeiffer
Ludwig Karl Georg Pfeiffer
Ludwig Karl Georg Pfeiffer, also known as Louis Pfeiffer was a German physician, botanist and conchologist.-Biography:He received his education in Kassel, and became professor of pathology there in 1828...
in 1837, the European tradition was to use Phyllocactus for epiphytic cacti with large regular flowers and Epiphyllum for the irregular-flowered species now called Schlumbergera truncata. Under modern rules, Phyllocactus is an illegitimate name, as is Epiphyllum in the sense of Pfeiffer; thus Epiphyllum Pfeiff. is a synonym of Schlumbergera. The true genus Epiphyllum
Epiphyllum
Epiphyllum is a genus of 19 species of epiphytic plants in the cactus family , native to Central America. Common names for these species include orchid cacti and leaf cacti, though the latter also refers to the genus Pereskia....
Haw. now has around 19 species.
Species
Six species are currently recognized. Only synonyms which have been widely used (and their basionymBasionym
Basionym is a term used in botany, regulated by the International Code of Botanical Nomenclature...
s) are given in the list below.
- Schlumbergera kautskyiSchlumbergera kautskyiSchlumbergera kautskyi is a species of plant in the Cactaceae family. It is endemic to a small area of the coastal mountains of south-eastern Brazil where its natural habitat is rocky areas. It is threatened by habitat loss...
(Horobin & McMillan) N.P.Taylor- syn. S. truncata subsp. kautskyi Horobin & McMillan
- Schlumbergera microsphaericaSchlumbergera microsphaericaSchlumbergera microsphaerica is a species of plant in the Cactaceae family. It is endemic to a limited area of the coastal mountains of south-eastern Brazil where its natural habitat is rocky areas above . It is threatened by habitat loss...
(K.Schum.) Hoevel- syn. Cereus microsphaerica K.Schum., Epiphyllanthus microsphaericus (K.Schum.) Britton & Rose, Cereus obtusangulus K.Schum., Epiphyllanthus obtusangulus (K.Schum.) A.Berger, Zygocactus obtusangulus (K.Schum.) Loefgr., S. obtusangula (K.Schum.) D.R.Hunt
- Schlumbergera opuntioidesSchlumbergera opuntioidesSchlumbergera opuntioides is a species of plant in the Cactaceae family. It is endemic to the coastal mountains of south-eastern Brazil where its natural habitats are humid forests and rocky areas. It is threatened by habitat loss...
(Loefgr. & Dusén) D.R.Hunt- syn. Epiphyllum opuntioides Loefgr. & Dusén, Zygocactus opuntioides (Loefgr. & Dusén) Loefgr., Epiphyllanthus opuntioides (Loefgr. & Dusén) Moran
- Schlumbergera orssichianaSchlumbergera orssichianaSchlumbergera orssichiana is a species of plant in the Cactaceae family. It is endemic to a small area of the coastal mountains of south-eastern Brazil where its natural habitat is moist forest. It grows on trees as an epiphyte...
Barthlott & McMillan
- Schlumbergera russellianaSchlumbergera russellianaSchlumbergera russelliana is a species of plant in the Cactaceae family. It is endemic to a small area of the coastal mountains of south-eastern Brazil where its natural habitat is moist forest. It grows on trees as an epiphyte...
(Hook.) Britton & Rose- syn. Epiphyllum russellianum Hook., S. epiphylloides Lemaire, nom. illeg.
- Schlumbergera truncataSchlumbergera truncataSchlumbergera truncata is a species of plant in the Cactaceae family. It is endemic to a small area of the coastal mountains of south-eastern Brazil where its natural habitats are subtropical or tropical moist forests...
(Haw.) Moran- syn. Epiphyllum truncatum Haw., Zygocactus truncatus (Haw.) K.Schum., nom. illeg.
Four hybrids have been named, all made in cultivation (although the first may possibly occur in the wild). The International Code of Nomenclature for Cultivated Plants
International Code of Nomenclature for Cultivated Plants
The International Code of Nomenclature for Cultivated Plants regulates the names of cultigens...
recommends that cultivated plants should be named under its rules, not those appropriate for natural species and hybrids. The Group names given below were provided by McMillan and Horobin.
- Schlumbergera × buckleyi (T.Moore) Tjaden = S. russelliana × S. truncata; S. Buckleyi Group
- syn. Epiphyllum buckleyi T.Moore, E. rollissonii T.Moore, S. bridgesii (Lemaire) Loefgr.
- Schlumbergera × eprica Süpplie = S. orssichiana × S. russelliana
- Schlumbergera × exotica Barthlott & Rauh = S. truncata × S. opuntioides; S. Exotica Group
- Schlumbergera × reginae McMillan = S. truncata × S. orssichiana; S. Reginae Group
Distribution, habitat and ecology
Schlumbergera occurs only in the coastal mountains of south-east BrazilBrazil
Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...
, in the states of São Paulo
São Paulo (state)
São Paulo is a state in Brazil. It is the major industrial and economic powerhouse of the Brazilian economy. Named after Saint Paul, São Paulo has the largest population, industrial complex, and economic production in the country. It is the richest state in Brazil...
, Rio de Janeiro
Rio de Janeiro (state)
Rio de Janeiro is one of the 27 states of Brazil.Rio de Janeiro has the second largest economy of Brazil behind only São Paulo state.The state of Rio de Janeiro is located within the Brazilian geopolitical region classified as the Southeast...
, Minas Gerais
Minas Gerais
Minas Gerais is one of the 26 states of Brazil, of which it is the second most populous, the third richest, and the fourth largest in area. Minas Gerais is the Brazilian state with the largest number of Presidents of Brazil, the current one, Dilma Rousseff, being one of them. The capital is the...
and Espírito Santo
Espírito Santo
Espírito Santo is one of the states of southeastern Brazil, often referred to by the abbreviation "ES". Its capital is Vitória and the largest city is Vila Velha. The name of the state means literally "holy spirit" after the Holy Ghost of Christianity...
. Sites where it has been found range from close to the Tropic of Capricorn
Tropic of Capricorn
The Tropic of Capricorn, or Southern tropic, marks the most southerly latitude on the Earth at which the Sun can be directly overhead. This event occurs at the December solstice, when the southern hemisphere is tilted towards the Sun to its maximum extent.Tropic of Capricorn is one of the five...
northwards to 20°S
20th parallel south
The 20th parallel south is a circle of latitude that is 20 degrees south of the Earth's equatorial plane. It crosses the Atlantic Ocean, Africa, the Indian Ocean, Australasia, the Pacific Ocean and South America....
, i.e. in the southernmost part of the tropics. Plants grow at altitudes from 700 metres (2,296.6 ft) in the case of S. truncata to 2780 metres (9,120.7 ft) in the case of S. microsphaerica, in either the coastal moist forests
Serra do Mar coastal forests
Biome: Tropical and subtropical moist broadleaf forestsRealm: NeotropicalWWF ID: NT0160Size: 104,800 square kilometers...
or rocky areas. The natural distribution of Schlumbergera species has become confused because European cultivars were deliberately introduced into some areas, including the Parque Nacional da Serra dos Órgãos, by the Brazilian Agricultural Department, to compensate for over-collecting of wild plants.
Because of their height and proximity to the Atlantic Ocean, the coastal mountains produce high altitude moist forests – warm moist air is forced upwards into higher, colder locations where it condenses. Schlumbergera species grow in habitats which are generally relatively cool, shaded and of high humidity. David Hunt describes collecting specimens in conditions of cloud, drizzle and overnight temperatures down to -4 °C. Plants are epiphytic or lithophytic, growing on moss-covered tree branches or in rock crevices, often in small pockets of substrate formed from decayed leaves and other vegetation. S. microsphaerica is found at higher altitudes, above 2200 metres (7,217.8 ft), in barren rocky habitats, and tolerates higher light levels.
The flowers of Schlumbergera have adaptations for pollination by hummingbird
Hummingbird
Hummingbirds are birds that comprise the family Trochilidae. They are among the smallest of birds, most species measuring in the 7.5–13 cm range. Indeed, the smallest extant bird species is a hummingbird, the 5-cm Bee Hummingbird. They can hover in mid-air by rapidly flapping their wings...
s: tubular flowers with abundant nectar, and colours towards the red end of the spectrum. Most species require cross-pollination
Allogamy
Allogamy is a term used in the field of biological reproduction describing the fertilization of an ovum from one individual with the spermatozoa of another. By contrast, autogamy is the term used for self-fertilization. In humans, the fertilization event is an instance of allogamy...
to set seed. The exceptions are S. kautskyi and S. microsphaerica; as noted above, the latter is found at higher altitudes where humming birds may be absent or less common.
The fruits of Schlumbergera do not open spontaneously when ripe, and appear to be adapted for distribution by birds, which eat the seeds and pulp contained in the fruit. Birds have been observed removing seeds which had stuck to their beaks by rubbing them on tree branches, where the seeds might be able to germinate. Segments may also break off from the stems and take root, thus enabling plants to propagate vegetatively.
History
Schlumbergera truncata was in cultivation in Europe by 1818. S. russelliana was introduced in 1839. Hybrids between the two, now called S. × buckleyi, were made in England by W. Buckley and first reported in 1852. By the 1860s a substantial number of cultivarCultivar
A cultivar'Cultivar has two meanings as explained under Formal definition. When used in reference to a taxon, the word does not apply to an individual plant but to all those plants sharing the unique characteristics that define the cultivar. is a plant or group of plants selected for desirable...
s (cultivated varieties) were available in a range of colours and habits, and were used as ornamental plants in "stoves" (heated greenhouse
Greenhouse
A greenhouse is a building in which plants are grown. These structures range in size from small sheds to very large buildings...
s) and in houses, where they were popular for their autumn and winter flowering. Many cultivars were selected seedlings of S. truncata, but at least three S. × buckleyi hybrids were available, of which one, now called S. 'Buckleyi', is thought to be the original Christmas Cactus. By the early part of the 20th century, the genus had become less popular, and many of the early cultivars were lost.
From around the 1950s onwards, breeding resumed in Europe, North America, Australia and New Zealand. New plants were produced by crossing among the species and existing cultivars of S. truncata, S. russelliana and the hybrid S. × buckleyi. Treatments which induced mutation
Mutation
In molecular biology and genetics, mutations are changes in a genomic sequence: the DNA sequence of a cell's genome or the DNA or RNA sequence of a virus. They can be defined as sudden and spontaneous changes in the cell. Mutations are caused by radiation, viruses, transposons and mutagenic...
s were also used. The result was a wide range of flower colours which had not been available before, including the first true yellow to be sold commercially, S. 'Gold Charm' (which was a sterile triploid). Breeders aimed for plants which grew strongly, were upright at the point of sale rather than pendulous, had many flowers or buds, and were adapted to living as house plants.
In the 1980s the species S. orssichiana was also used in crosses. The hybrid of S. truncata and S. orssichiana has been named S. × reginae or S. Reginae Group; one of the first cultivars was S. 'Bristol Queen'. S. opuntioides crosses have also been made, but have not resulted in commercially available cultivars.
Modern cultivars
McMillan and Horobin have listed hundreds of modern European, North American and Australian cultivars, which they put into a number of cultivar groups:- The Truncata Group contains all cultivars with mainly S. truncataSchlumbergera truncataSchlumbergera truncata is a species of plant in the Cactaceae family. It is endemic to a small area of the coastal mountains of south-eastern Brazil where its natural habitats are subtropical or tropical moist forests...
characteristics: stem segments with pointed teeth (dentate); zygomorphic flowers held more or less horizontally, usually above the horizontal; and pollen which is yellow. - The Buckleyi Group contains all cultivars with at least some features clearly showing inheritance from S. russellianaSchlumbergera russellianaSchlumbergera russelliana is a species of plant in the Cactaceae family. It is endemic to a small area of the coastal mountains of south-eastern Brazil where its natural habitat is moist forest. It grows on trees as an epiphyte...
: stem segments with rounded, more symmetical teeth (crenate); more regular flowers which hang down, below the horizontal; and pollen which is pink. There is considerable variation within this Group; McMillan and Horobin introduced subcategories: "TB" for those more like S. truncata and "BT" for those more like the classic S. × buckleyi, with "B" reserved for the first generation (F1) S. × buckleyi hybrids. - The Reginae Group contains cultivars known to be derived from hybrids with S. orssichianaSchlumbergera orssichianaSchlumbergera orssichiana is a species of plant in the Cactaceae family. It is endemic to a small area of the coastal mountains of south-eastern Brazil where its natural habitat is moist forest. It grows on trees as an epiphyte...
. - The Exotica Group is used for the small number of hybrids involving S. opuntioidesSchlumbergera opuntioidesSchlumbergera opuntioides is a species of plant in the Cactaceae family. It is endemic to the coastal mountains of south-eastern Brazil where its natural habitats are humid forests and rocky areas. It is threatened by habitat loss...
.
Attempts have also been made to classify cultivars by colour. A difficulty is that the flowers of many cultivars exhibit different colours depending on the temperature during bud formation and growth. In particular, temperatures below 14 °C (57.2 °F) produce pink tones in otherwise white and yellow cultivars, and strengthen the colour in pink and red cultivars. The availability of iron to the plant has also been suggested to affect flower colour.
In the United States, cultivars are propagated in large numbers for sale before Thanksgiving Day
Thanksgiving (United States)
Thanksgiving, or Thanksgiving Day, is a holiday celebrated in the United States on the fourth Thursday in November. It has officially been an annual tradition since 1863, when, during the Civil War, President Abraham Lincoln proclaimed a national day of thanksgiving to be celebrated on Thursday,...
(the fourth Thursday in November). In Europe, plants are mainly sold later in the year, in the period before Christmas
Christmas
Christmas or Christmas Day is an annual holiday generally celebrated on December 25 by billions of people around the world. It is a Christian feast that commemorates the birth of Jesus Christ, liturgically closing the Advent season and initiating the season of Christmastide, which lasts twelve days...
. A single Dutch grower (de Vries of Aalsmeer
Aalsmeer
Aalsmeer is a municipality and a town in the Netherlands, in the province of North Holland. Its name is derived from the Dutch for eel and lake . Aalsmeer is bordered by the Westeinderplassen lake, the largest open water of the Randstad, and the Ringvaart Canal...
, Holland) was reported in 1989 as producing 2,000,000 plants per year.
Common names
Plants are offered for sale under a variety of common names. The earliest English common name was "Christmas Cactus". In Europe, where plants are largely produced for sale in the period before Christmas, this remains the most widely used common name in many languages for cultivars of all groups (e.g. in German, in French, and in Spanish). This is also the name used in Canada. In the United States, where plants are produced for the Thanksgiving holiday in November, the name "Thanksgiving Cactus" is used; "Christmas Cactus" may then be restricted to cultivars of the Buckleyi Group, particularly the very old cultivars such as 'Buckleyi'. The name "Crab Cactus" (referring to the clawed ends of the stems) is also used for the Truncata Group. "Link Cactus" is another common name, describing the way that the stems of the genus as a whole are made up of linked segments.The Easter Cactus or Whitsun Cactus is now placed in the genus Hatiora
Hatiora
Hatiora Britton & Rose is a small genus of epiphytic cacti which belongs to the tribe Rhipsalideae within the subfamily Cactoideae of the Cactaceae...
, but was at one time included in Schlumbergera (or one of its synonyms). The name "Holiday Cactus" has been used to include both Schlumbergera and Hatiora cultivars.
Care of cultivars
When grown as house plants, Schlumbergera cultivars are said to be relatively easy to care for. McMillan and Horobin describe in detail their cultivation in both commercial and domestic conditions. Their specific recommendations include:- Growing medium Free-draining, humus-rich, somewhat acid growing media are used commercial production, such as a mixture of peatPeatPeat is an accumulation of partially decayed vegetation matter or histosol. Peat forms in wetland bogs, moors, muskegs, pocosins, mires, and peat swamp forests. Peat is harvested as an important source of fuel in certain parts of the world...
or leafmould and an inert material such as grit, sharp sand or polystyrene beads. It is recommended that plants should be grown in relatively small pots; half-height pots are suitable. - Watering They are more tolerant of drought than many house plants, but can be damaged by both under- and over-watering. Keeping the growing medium just moist throughout the year avoids either extreme.
- Light They can be damaged by exposure to more than small amounts of sunlight. Members of the Buckleyi Group, such as the old-fashioned Christmas Cactus with pendant flowers, are more tolerant of high light levels than members of the Truncata Group, such as most of the modern cultivars. Too much light causes stems to take on a reddish colouration; however, very low light levels will prevent flowering. Day length is important in controlling flowering; continuous darkness for at least 12 hours is necessary to induce bud formation. A period of about 8 days with 16 hours of darkness at 16 °C (60.8 °F) has been shown to cause flower buds to form. Lower temperatures slow this process. The advice sometimes given to withhold water to produce flower buds has been shown to be incorrect.
- Propagation Both commercially and in the home, propagation can be achieved by using short pieces of stem, one to three segments long, twisted off rather than cut. Cuttings are allowed to dry for 1–7 days, forming a callusCallus (cell biology)Plant callus is a mass of undifferentiated cells derived from plant tissue for use in biological research and biotechnology. In plant biology, callus cells are those cells that cover a plant wound. To induce callus formation, plant tissues are surface sterilized and then plated onto in vitro...
at the broken end, and then rooted in an open growing medium. Temperatures above 21 °C (69.8 °F) and up to 27 °C (80.6 °F) in long day/short night conditions speed rooting.
External links
- Schlumbergera growing information, species, cultivar varieties, pictures and videos
- A time lapse photography video of a Schlumbergera flower blossoming out. The video has been shot during 4 days and 3 nights and has been squeezed into under 4 minutes of playback time (1000x real time).