Christmas cactus (Schlumbergera bridgesii) and Thanksgiving cactus (Schlumbergera truncata) look exotic but are rather easy to maintain with the right growing conditions. While in bloom, water the plants when the soil surface is just becoming dry to the touch. Never let the plants remain in standing water and well-drained soil is a must.
Holiday cacti bloom in response to the shorter days and cooler nights we experience heading into winter. If you are gifted a Christmas cactus this season, to prolong the bloom, keep the daytime temperature between 60-65 degrees F and the nighttime temperature between 55-65 degrees F. Keep your cactus in total darkness for at least 12 of every 24 hours. The plant should receive bright, indirect light for the rest of the time. Sudden changes in temperature can cause the cactus to drop its blooms. When transporting it home be mindful of the outdoor temperature and take measures to protect your plant from the cold.
The segments of the holiday cactus that look like leaves are actually stems known as “phylloclades”. When your cactus finishes blooming, you can prune it at the union of two of these segments. Each cut phylloclade remaining on the parent plant will produce one to two new stem segments. This will encourage branching and a fuller plant. The cuttings removed from the plant can be propagated into new plants. Dip the cut-end of the stem into water and then rooting hormone, which can be purchased at garden centers or online. Secure this end into potting mix and keep it moist and in a warm location with bright light. Once roots develop you can transplant it into a cactus/succulent media.
While the parent plant is not blooming, decrease the water and care for it as you would a typical houseplant. When the danger of frost has passed, holiday cacti can be moved outdoors in part shade. Beneath a tree is a great location that will provide filtered light. If the stems begin to turn pale they may be receiving too much light. Fertilize once each month in June, July and August at half-strength with a balanced houseplant fertilizer. As the temperature drops to the low 50s at night bring your cactus back indoors. When flower buds begin to develop switch to a fertilizer low in nitrogen and higher in phosphorus and potassium.
Cynthia Domenghini, Extension Agent