Here’s what you can do to help your Christmas Cactus bloom.
This plant needs a temperature range of 55-70 degrees F. If temperatures rise higher or lower, then you may encounter blooming problems.
The amount of light (or more specifically darkness) it receives will affect the blooming. To make sure your Christmas cactus blooms in time for Christmas, you must keep your cactus in an area that is cool and dry during mid-September to mid-November until flower buds appear. During this time, the Christmas cactus should not receive more than 11 hours of light during the day. It needs to be in a spot that has bright light with no direct sun during the day and uninterrupted darkness at night.
Keep any artificial light sources away from the Christmas cactus, which can interfere with the dark period. You can place a box over it at night to help the process of blooming. When in bloom, water it normally. Be sure to give the plant a rest period after blooming, which means less watering during February and March.