by Cristina Malinverno, Blauvelt Master Gardener
Common causes of bud dropping of Christmas cactus (Schlumbergera truncata), also known as Thanksgiving cactus, are over watering, cold drafts, or closeness to a heat source. Since this is a succulent plant, the frequency of watering depends on the air temperature, light intensity, rate of growth, and relative humidity. In general, watering should ease off as soon as the flower buds appear, until growth resumes in the spring.
Christmas cactus (Schlumbergera truncata), a plant native to Brazil where it blooms in May (hence the local nickname “May flower”). Christmas cacti thrive in shady conditions or filtered light, in a soil mix that includes garden loam, perlite and builder’s sand combined in a 3:1:1 ratio or a commercial mix for succulent plants.
Unlike the poinsettias, which require a strict horticultural regimen in order to bloom again the following year, Christmas cacti are simple to care for. After blooming, gently remove any spent flowers and lightly prune to encourage growth and shape the plant. Older plants may require the use of clippers, while in young plants you can gently twist off unwanted stem segments; this will prompt two new stem buds to form.
Decreasing sunlight and temperature in the fall prompt the setting of flower buds. To ensure a profusion of flower buds, cover the plant at night or move it to a cool, dark room with temperature around 60 degrees. Once the buds have appeared, night light is no longer a problem and you can move the plant to its final location, possibly an east or northeast-facing window. In cool temperatures the flowers will last a few weeks.
