Christmas cactus – care and propagation

This question is heard again and again when these decorative plants are offered in the flower trade – Christmas associations of cold and wet and images of heat and dryness that come up when thinking about cacti do not really go together.

The Christmas cactus does indeed come from warm regions, but rather from “the opposite of desert”. The “Schlumbergera”, botanically named after its discoverer, the cactus collector Frédéric Schlumberger, belongs to the cactus family.However, the Schlumbergera are native to Brazil. They grow in some states in south-eastern Brazil in the “Mata Atlântica”, the Atlantic rainforest, right up to the mountains near the coast. The climate there is tropical to temperate and quite humid, with not very significant seasonal temperature fluctuations and with temperatures that never really drop below 15 degrees. This colder period is between May and September in the homeland of the Schlumbergera, while in this part of Brazil the average temperature is 20 degrees from October to April, with peaks of around 24 degrees in December, January and February.

In this comfortable climate, the different species of Schlumbergera have settled in the middle of the trees of the rain forest or on rocks of the coastal mountains. In their natural environment, they like to colonize the tops of trees as epiphytes or “dig” themselves into the crevices of the rock masses of a mountain range as lithophytes. Despite these unusual growth forms, they usually manage to develop into real small shrubs with numerous shoots that branch out very profusely. At the tips of these shoots, the blossoms stretch towards the light. They form a lush variety of colors in the tropical sun, purples and pinks, reds and oranges, yellows and whites.

We call the Christmas cactus the Christmas cactus because it also shows its flowers here in the Brazilian summer, i.e. around Christmas here.

Different varieties

The Schlumbergera form a separate genus of plants in the Cactaceae family, which includes only half a dozen species:

• Genus was named after Schlumbergera russelliana or Schlumbergera epiphylloides
  • flowers pink, with slightly bell-shaped hanging flowers
  • grows epiphytic in nature, i.e. climbs up trees
  • grows mainly in Rio de Janeiro at heights between 1.5 and around 2 km
• Schlumbergera kautskyi grows in the neighboring state of Espírito Santo
  • inhabits low altitudes between almost 1 and 1.3 km
  • was discovered in 1991
  • is considered a rare species and is classified as “Endangered (EN)” in the “Red List of Threatened Species”.
• Schlumbergera microsphaerica grows in two slightly different subspecies mainly in Rio de Janeiro
  • he climbs up to almost 3,000 meters
  • Blossoms hang too
  • Develop colors from fuchsia red to white
  • S. microsphaerica is listed as threatened in the Red List of Threatened Species
• Schlumbergera opuntioides in the “Red List”, classified only as “Near Threatened (NT)”.
  • distributed in Rio de Janeiro and adjacent states of São Paulo and Minas Gerais
  • Flower colors between pink and purple
• Schlumbergera orssichiana develops very unusual flowers
  • white bracts adorned with crimson flames at the edges and tips
  • found in northwest Rio de Janeiro and east of São Paulo at altitudes between 1.5 and 2.5 km
  • a rather rare species
• Schlumbergera truncata is content in Rio de Janeiro with altitudes of 700 to 1000 meters
• white, red, pink or orange flowers not only droop, but also show growth clad towards the light

In the meantime, some important cultural hybrids have been bred, which have been given their own names:

• Schlumbergera × buckleyi
  • Hybrid of S. russelliana and S. truncata, from which it took over the partly erect flowers.
• Schlumbergera × exotica
  • Hybrid of S. opuntioides and S. pleases with imaginative flower colors
• Schlumbergera x Queen
  • Hybrids of S. orssichiana and S. truncata

The Bud Formation

What all varieties and hybrids have in common is that they are so-called short-day plants. They set their flowers in Brazil at a time when the days are shortest there. From May to September, in Brazil, which is close to the pole, the day lasts no more than 11 hours. The Schlumbergera bloom in the Brazilian summer, i.e. December, January and February. The time of bud formation is before, July to November, our summer and autumn.

Each plant is thus stimulated by very specific temperatures and day lengths to engage in flowering. Due to other very specific temperatures and day lengths, not to concern yourself with the formation of flowers, but rather to eagerly train new shoots. In Brazil, the Schlumbergera starts budding with day lengths around 11 hours and temperatures around 15 degrees. With day lengths of around 13 hours and temperatures above 23 degrees, no buds are formed, only new shoots.

Regardless of this, what always applies to a Christmas cactus in our country is its need for light, which is rarely satisfied in Germany. Every Christmas cactus should therefore be outside in the summer season. Here he gets to know at least part of the light intensity that he is used to in Brazil.

In addition, if you cultivate a plant in a climate that is completely different from its native climate, it will still behave similarly to its homeland in terms of bud formation and shoot formation.

For the keeping of the Schlumbergera in Germany, this means: For the formation of buds in our summer/autumn, it needs a time in which it is ideally exposed to temperatures of around 15 degrees, with the shortest possible day length. A Christmas cactus should therefore remain outside with us until it has gone through a few colder days (or at least nights) with a significantly reduced day length. Depending on the climate in your home region, the Christmas cactus can remain outdoors until October or even November.

If it is kept (continuously or only in winter during flowering) at temperatures above approx. 23 degrees, it will only form new shoots (and no buds). No matter how short or long the days are, the temperature is the decisive criterion here. So if a Christmas cactus is kept all year round in an apartment where it is always nice and warm, it will only ever produce new shoots and never buds.

The day length-temperature scheme for stimulating bud formation can be put a little more precisely:

• If the Christmas cactus is exposed to temperatures between 17 and 20 degrees for short days from around the beginning of October (possibly only at night), buds will probably form.
• If a Christmas cactus is kept in autumn with night time temperatures between 10 and 15 degrees, it will also probably bud, regardless of the length of the day.
• If the Christmas cactus often has to endure temperatures below 10 degrees during this time, no buds will be formed – and the whole plant does not like such cold.

outdoor location

However, the advice on staying outside isn’t just about giving your Christmas cactus a “special fall outdoor treatment” if you ever want to see the pretty blooms.

It also benefits so much from being outdoors in other respects that it should be put outside as soon as the outside temperature is between 15 and 17 degrees during the day and does not fall below 10 degrees at night. The light outside is several powers more intense than the light in the living room. In this environment, the plant simply grows better all around. The newly attached shoots will mature well. The whole plant goes into the winter, into the strenuous flowering period, healthier and more resilient.

During the budding period, the Schlumbergera should be kept a little drier. From about the beginning of September you give less water, but the root ball should never dry out completely. Fertilizer is now no longer necessary at all. If the first buds appear shortly before moving into the house, you can treat the plant to a small shot of fertilizer. It is also kept a little wetter again.

The care in the winter bloom

Only when your Christmas cactus has formed plenty of buds is it allowed (as a reward) into the warm room. So, depending on the region, not until November. Only when an autumn storm threatens to tear it to shreds on the balcony do you have to invite it into the living room for a few hours.

If you bring the Christmas cactus into the room, you should set it up so that the light falls on the plant at roughly the same angle. If the Schlumbergera suddenly gets light from the other side, it could irritate it so much that it quickly sheds all the buds. When the buds open, you could extend the flowering period of around three weeks by turning down the temperatures in the warm room a bit. If you can go down to 18 degrees, a Christmas cactus can bloom for up to a month and a half.

Once the flowering is over, you should allow the Christmas cactus to rest in a bright location with temperatures between 10 and 15 degrees. It is then kept a little drier again and not fertilized.

Pruning and propagation of the Christmas cactus

The care of a Christmas cactus is otherwise basically very simple. In the vegetative growth phase between March and August, the Schlumbergera need constant moisture, which is supplied with water that is as soft as possible (lime-free). If your tap water is too calcareous, it is better to use rainwater or leave the tap water in the watering can for about two weeks. A Christmas cactus that is constantly supplied with lime could gradually die off. Please make sure not to act too eagerly when watering. Too much water has probably killed more Christmas cacti than any other husbandry mistake. During the growth phase, the Christmas cactus regularly gets a little commercial flower fertilizer.

If you keep all of this in mind, your Christmas cactus will likely develop into a magnificent shrub for years to come. If it gets too big, simply twist off as many strong shoots from the mother plant as you want to trim the plant between April and July.

You can then immediately use these shoots to propagate your Christmas cactus. They are simply placed in water glasses or in pots with soil and should root quickly. This usually works very well with the Christmas cacti.

You can also try propagating from seeds. Your Christmas cactus would have to set fruit for this. You can then leave these fruits on the plant until they burst open or (when slightly dried) can be easily removed. Inside these fruits are tiny oval, brown or black seeds that you can pick out. The seeds are freed from the pulp, stored in a cool and dry place for a while and sown in the normal way in seed soil in the spring.

Conclusion
Once you have found out about the special husbandry cycle of the Christmas cactus and treat the plant accordingly, your Schlumbergera will also show itself to be an easy-care, undemanding and long-lived (room) comrade in this country, who will delight you with extraordinary flowers, especially in winter.