Christmas cactus (Schlumbergera bridgesii) is a lovely plant commonly given during the winter holiday season. Not to be confused with the other popular varieties of Schlumbergera, including Thanksgiving cactus (Schlumbergera truncate) and Easter cactus (Schlumbergera gaertneri), the Christmas cactus blooms during the winter as the day length shortens and evening temperatures decrease. Without proper care, the Christmas cactus may not bloom regularly or at all.
The Christmas cactus is native to the rainforest. This is unusual for cacti which are commonly found in desert environments. However, Christmas cacti prefer high humidity and bright, filtered light. During the summer months they can thrive under the canopy of a tree outdoors, which mimics the rainforest environment. While outdoor temperatures remain below 50 degrees, keep your Christmas cactus indoors by a window where it will receive indirect light. The window should be draft-free and prevent the leaves of the cactus from touching the glass or they could be damaged from the cold.
In order to bloom, Christmas cacti require at least eight hours of bright, indirect light, 12 hours of complete darkness and evening temperatures between 60 to 68 degrees, although closer to 68 degrees is best. When your Christmas cactus starts to bloom avoid moving it. Sudden changes in temperature or light can cause the flowers to drop and abruptly end the bloom season.
If you received a Christmas cactus during the recent holiday season it is unlikely it will need to be repotted for two to three years. While they do require good soil drainage, Schlumbergera perform well when grown in a container that is somewhat restricting in size. As with other cacti and succulents alike, large containers can retain too much water and allow the roots to rot.
Christmas cactus should only be watered when the soil is dry. Overwatering will cause the plant to wilt and potentially die. Allow the water to drain from the container rather than stored in a saucer or in the soil. Standing water will drown the roots and damage the plants. After blooming, Christmas cacti do not require much water until the active growth begins again in the spring.
Growing plants indoors can invite pests. A common small flying insect found in homes with houseplants is the fungus gnat. These pests prefer wet soil, so a first step to remedy the situation is to allow the soil of your indoor plants to dry. You can also re-pot your houseplants with fresh, sterile potting mix to remove any soilborne pests.
If you enjoy growing Schlumbergera you can propagate additional plants at the end of spring by pinching back the plant into sections with three to five stem segments intact. Lay the segments outside for a couple of days to form a callous over the cut ends before potting them in small containers with sterile potting mix. Cuttings should be planted 1 inch deep and then watered well. Enclose the plants and container with a clear plastic bag and seal with a rubber band. This creates a humid environment that will promote rooting. Roots should form within one to two months at which time the plastic bag can be removed.
Next year you will be prepared to gift Christmas cacti to your friends and family along with the information they need to have beautiful blooms for years to come. Indoor gardening is a great way to bridge the gap from one growing season to the next.
Cynthia Domenghini is an instructor and coordinator for K-State’s horticultural therapy online certificate program.