Imagine a mountainous and remote rainforest with a coastline. Whispers of fog flow through the trees as cascades of colorful flowers come down from tall plants on tree limbs. It is the Mata Atlantica or Atlantic Forest of Brazil, a biodiversity hotspot and the birthplace of the Christmas cactus or Flor de Mao (May flower). In the Southern Hemisphere this plant blooms in May (autumn); In the Northern Hemisphere it blooms during the winter holidays, hence its popularity as a Christmas gift.
Christmas cactus is a common name given to a small group (genus) of cacti, called Schlumbergera, which are native to the coastal mountains of southeastern Brazil, which grow mostly in high altitude, moist forests where conditions are relatively cool. are shaded and humid. In the wild, Schlumbergera are either epiphytic or lithophytic, meaning that they grow either on moss-covered tree branches or in crevices of rock filled with rotten leaves and other vegetation rather than on the ground.
These plants are true members of the cactus (Cactaceae) family, even though they bear little resemblance to other species of cacti adapted to the desert heat: they have leaves instead of branches and photosynthetic stems instead of areoles.
Despite their cool and moist native habitat, these plants are hardy and grow well in a pot next to a window in a sheltered patio or indoors in bright, indirect light. With proper cultivation, they also live longer; Schlumbergera can live up to 50 years or more; Has been passed on as a cherished heirloom in many families.
Amazingly, a “Christmas cactus” may be one of three different species. Schlumbergera truncata blooms earlier, usually in November, and is more accurately called the Thanksgiving cactus. Schlumbergera xbucklyi (sometimes referred to as S. bridgesii) blooms later, often in December or January (hence the “Christmas cactus”). Finally, there is the Schlumbergera gaertneri (formerly classified as Hatiora gaertneri or Rhipsalidopsis gaertneri) that blooms in the spring, around Easter, and again later in the year (P.Geisel and C.Unruh, Holiday Cacti, Publication 8114, UC Regents, 2004 )
The common and botanical names given to these plants can be confusing, and the label of “Christmas cactus” can be given to any of them. So how can you identify which species you have?
If the plant is in bloom, S. truncate’s flowers are zygomorphic (bilaterally symmetrical when cut lengthwise) more or less horizontally or horizontally above, and the pollen is yellow; Whereas the flowers of S. x Buckleyi are more regular and hang down horizontally, with pollen that is pink. s. The flowers of gartneri differ from the other two species in that they are radially symmetrical (actinomorphic) and open to a funnel shape, like a starburst.
If the plant is not blooming, the best way to identify which species you have is by looking at the stem segments (phylloclades) that make up the plant. s. truncata have teeth (dentate) in the stem segment, often with two large teeth at the end of the segment, whereas in S x buckyli they are rounded, with more symmetrical teeth (crenate); s. gartneri are very rounded, with small notches along the edge on the areoles. For useful illustrations of all these species, see “Is It a Thanksgiving, Christmas or Easter Cactus? – World of Succulents.”
Indeed, some sources claim that the Thanksgiving cactus Schlubergera truncata is actually widely marketed as a Christmas cactus.
a brief History
Christmas cacti have been given as holiday gifts since the late 19th century.
Charles Lemire, a French botanist, named the genus Schlumbergera in 1858, in memory of Friedrich Schlumberger, who had a collection of cacti in his chateau in France. Lemaire started with only one species in his new genus—a plant discovered in Brazil in 1837 that is now classified as Schlumbergera rouselliana.
The cultivation of Schlumbergera truncata (Thanksgiving cactus) began in Europe in 1818, and S. russelliana was introduced in 1839. The two species were deliberately crossed in England, resulting in the hybrid now called Schlumbergera × Buckleyi, first recorded in 1852, the true Christmas cactus.
Schlumbergera gaertneri (Easter cactus) was first described in 1884 as the variety gaertneri of Schlumbergera russelliana). The name honors one of the Gartner family of early settlers in Brazil.
These winter- and spring-blooming species are three of the seven recognized species within the genus Schlumbergera. In addition, there are hundreds of modern varieties of Christmas cactus (breeder-selected cultivars).
care and feeding
Schlumbergera cacti do best in temperatures of 50 to 70 degrees Fahrenheit, which makes them an obvious choice for a houseplant, but they can also live outside if they are sheltered from direct, intense sunlight, heat, and frost. These rainforest plants require moisture. An indoor environment such as a kitchen with bright indirect light is perfect, or you can provide moisture by misting the plant or placing the pot on a saucer of pebbles filled with water so that the plant benefits from evaporation but does not sit in water. In their native habitat, these plants can receive up to 17 inches of rain a month during their growing season (March through September).
Although this is reduced to 3 inches per month in dry climates, it is still enough to provide consistent moisture and humidity (Geizel and Unruh, holiday cacti). Since these plants grow naturally in tree branches or crevices of rocks, they prefer to live in small pots with tight roots. The potting mix should be loose and fast-draining; A good cactus mix that is somewhat acidic (pH 5.0 to 6.0) will work. Allow the Schlumbergera to dry out of the wart between waterings, but not completely. A good rule of thumb is to water when the top one to two inches of soil becomes dry (depending on the size of your pot). Fertilize every two to four weeks during the growing season using a well-balanced formulation such as 10-10-5. Liquid fertilizers or granular slow-release formulas mixed with water according to directions are equally effective. With proper care, these hardy plants are generally free from pests or disease.
bloom and spread
The most intriguing aspect of Schlumbergera cultivation is that they bloom profusely each year during the holiday season. Schlumbergera are thermophotoperiodic, meaning that temperatures and short days (a few hours of daylight) bloom. Even with good care, they will probably bloom less unless exposed to cool night temperatures (50 to 55 degrees) and 12 to 16 hours of total darkness a day, which is roughly past their flowering period. Begin six to eight weeks earlier.
In the fall, a sheltered spot outside will work as long as daylight is limited to 10 to 12 hours and nighttime temperatures drop into the 50s (but not more than 50 degrees). Indoors, a cool room where the lights don’t turn on at night is ideal; Another option is to keep the plant under a dark cloth or in a closet to ensure complete darkness from 5 pm to 8 am.
When flower buds are planted, keep the plant away from heater vents, fireplaces, and other sources of hot air; Persistently hot temperatures, especially above 80 degrees, can cause flower buds to drop. Once the plant blooms, make sure it is watered regularly, but do not fertilize.
Schlumbergera typically remains in flower for four to six weeks and then enters a rest period, followed by a new growth cycle. After flowering is a good time to cut and shape the plant. You can use the cut sections to start new plants easily. Let the cut ends dry for a few days (callus), and then plant them about 1 inch deep in moist, clean potting mix (5 cuttings in a 6-inch pot). The use of rooting hormone is usually not needed. Cover the pot or tray with a clear plastic bag to create a more humid environment, making sure the bag is up and away from the cuttings.
Although far from their original rainforest home, the exotic Schlumbergera cacti still brighten up our winter holidays with the gift of brilliant color and beauty.
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