Christmas cactus care: location, watering & fertilising

Christmas cactus care: location, watering & fertilising

In order for the Christmas cactus to bloom in full, the right care including proper location, fertilising and watering must be provided.

Christmas cactus: choosing the right location

The varieties of Christmas cactus (Schlumbergera x buckleyi), which are usually available for purchase during winter in specialist shops, are hybrids which have been created by crossing different wild species of the genus Schlumbergera. These cacti species are native to tropical and subtropical areas of Brazil. Accordingly, Christmas cactus does not like temperatures below 10 °C.

Due to the Christmas cactus’ tropical origin, it is best to keep it as a houseplant in regions with temperate climates. If the weather permits it in summer, it can of course be relocated outside to enjoy some warmth. However, it is best to place the cactus in a semi-shady location because the full sun does not agree with this plant. Once the temperatures start to fall again in autumn, the plant should be placed back inside in order to avoid damages inflicted by the cold.

These are the general rules that apply to the choice of the location for the Christmas cactus:

  • Temperatures below 10 °C should be avoided
  • Christmas cactus should be kept as a houseplant (most of the time) in temperate climate zones  
  • If the temperatures allow it, the cactus can spend the summer outside
  • Choose a place that is somewhat in the shade – the Christmas cactus does not tolerate direct sunlight

The Christmas cactus starts to form flowers in October. In order for the flowers to form fully, there are several measures that need to be taken. First, the Christmas cactus should be kept slightly cooler (around 15 °C) from October onwards. Second, at this stage it should not be exposed to daylight longer than 9 hours a day. We recommend placing the cactus in a special location where these conditions are ensured. As soon as the first flower buds are observable, the daylight supply as well as the temperature can be increased (up to 20 °C). These conditions can be maintained until the Christmas cactus moves to its summer quarters.

In order to let your Christmas cactus bloom in full glory, these measures should be taken:

  • To form flowers, lower the temperature (15 °C) and reduce the amount of light (short day: maximum 9 hours of daylight)
  • As soon as the flower buds form, move the plant to a bright location and let the temperature rise to 20 °C
  • Provide the Christmas cactus with a relatively bright and warm location until it can be relocated outside for the summer months.

Even if you intend to keep the Christmas cactus in a pot, the substrate plays a decisive role in the wellbeing of the cactus. One of the possible options is to use commercial potting soil, regardless if it contains peat or not. The most optimal pH value of the substrate for Christmas cactus is between 5.5 and 6.0. In addition, the substrate should be as permeable as possible, as the Christmas cactus reacts very sensitively to even the slightest amounts of stagnant moisture. The permeability can be easily achieved by adding sand to the substrate: use a 1 to 4 sand to substrate ratio.

Soil requirements of the Christmas cactus summarized:

  • Substrate: commercial potting soil, regardless if peat-free or not
  • pH value from 5.5 to 6.0 is optimal
  • Choose a substrate with a loose structure so that it is more permeable to water
  • Add sand to the substrate to increase the permeability of the substrate and thus counteract waterlogging (use a 1 to 4 sand to substrate ratio)

Watering Christmas cactus properly

In short, the demand for water strongly depends on the development phase of the Christmas cactus. During bloom, the cactus should be watered approximately once a week, depending on the room temperature. In the resting phase that follows the bloom, frequent watering is unnecessary. Just make sure that the cactus does not dry out completely. The growth of new shoots indicates the beginning of a new growth phase. At this stage, the cactus’ need for water increases, which is why it should be watered more often.

If the Christmas cactus is kept outside for the summer, it should be watered ideally every two to three days. However, it is advised to place the cactus in a sheltered place where it won’t get rained on as that could lead to waterlogging. The substrate should be kept moderately but evenly moist. Neither extreme – too dry or too wet – have a positive effect on the growth of the Christmas cactus. During the resting phase before flowering, the watering can be halted completely.

This is the summary of what to keep in mind when watering the Christmas cactus:

  • Water regularly during flowering (approx. once a week)
  • Keep the substrate evenly moist and do not let it dry out
  • In summer, keep the cactus outside but sheltered from the rain
  • During the main growth stage, water the cactus every 2 or 3 days
  • During the resting phase before bloom (from October), reduce or completely avoid watering

Fertilising Christmas cactus properly

The Christmas cactus should only be fertilised during the main growing phase (April to September). There is no need to fertilise when the cactus is in bloom or any other time. An easy way to do that is to purchase a multiple-nutrient fertiliser from your local gardening centre. Usually, there are two options available: either organic or mineral fertiliser.

If you decide on the organic fertiliser, pick the liquid version. In this form, the nutrients are available to the plant more quickly than if, for example, horn shavings or compost were used. In any case, follow the instructions on dosage as stated on the instruction manual or on the packaging of the respective fertiliser – regardless whether organic or mineral fertiliser is used. Using these instructions, fertilise the Christmas cactus every four weeks during the main growth phase (April to September).

In general, this is how the Christmas cactus should be fertilised:

  • No fertilisation required during bloom, resting period before flowering (from October) and the time between flowering and the formation of new shoots
  • Fertilise the Christmas cactus between April and August/September (the main growth phase)
  • Use multiple-nutrient fertilisers – mineral or organic
  • Read the instruction manual of the purchased fertiliser
  • Fertilise every 4 weeks during the growth phase

Leave a Reply

Your email address will not be published. Required fields are marked *