Christmas cacti need special care now, in mid autumn, to be able to produce flowers in December. Buds will form when temperatures are between 10-15 Celsius degree (50-60 F), or if the plant is exposed to at least 13 hours of complete darkness each night. Putting them in a spare room will worth the extra effort it may take for the spectacular display of pink or red blooms depending on the cultivar, that is sure to follow.
Once the flowers are starting to show you must avoid moving the plant from it’s place and try to maintain the optimum temperature, else it will loose the flowers and all the wait and effort will prove to be useless.
If you give the right treatment to the Christmas cacti you will have it as companion for 15 to 20 years. Find a place for it on a suspended shelf so you can admire it’s pendent port, in a place with strong light but away from direct sun, preferably near a North window.