Christmas Cactus (Schlumbergera truncate) is a well-loved succulent that is native to the tropical forests of Brazil.
One of the few plants to bloom during the holiday season, Christmas Cactus has earned a place with Poinsettias and Holly as a seasonal staple, thanks to its long bloom period and profusion of white, pink, purple, and red flowers.
It can be quite disappointing when this plant fails to bloom, and those who haven’t grown it before often aren’t aware that there are a couple of conditions that must be met before their Christmas Cactus will reward them with its trademark floral display.
Because most people purchase Christmas Cactus when they are in bloom or right before their bloom season, they often don’t know how to get them to bloom the next year, winding up disappointed when the plants that were so beautiful the previous holiday season fail to perform. Fortunately, it doesn’t have to be that way. Here’s what you need to know about getting this plant to bloom.
Temperature is one of the most important factors in promoting healthy blooms on Christmas Cactus. The key is to mimic the plant’s natural environment as closely as possible.
Because Christmas Cactus blooms during the winter months, it needs relatively cool temperatures in order to initiate bud and flower production.
About six to eight weeks before the first buds should be beginning to form on your Christmas Cactus, place it in a cool room where temperatures remain under 61 degrees.
This is probably the most important factor in ensuring the best possible floral display from your Christmas Cactus. The trick is to make sure it receives from between 12 and 14 hours of total darkness during each 24-hour time period starting from six to eight weeks.
This should not be a room in which light gets turned on and off throughout the course of the evening — even just a small of light for a short period of time can throw off the plant’s internal clock and have a negative effect on bud production.
During this time period, your Christmas Cactus plant needs about eight hours per day of bright, indirect light. You may have to move it back and forth between two rooms for the period leading up to bud and bloom production, but if you’ve got the right kind of room in your home, all you need to do is place it on a windowsill.
The room should have either north or east-facing windows — southern and western exposures may provide too much direct sunlight, especially if you live in a southern state. If this is the only available room you have, put up a pair of semi-transparent curtains.
You should also stop watering your Christmas Cactus at the same time you move it into a cooler environment to help prepare it for its bloom season. For most people, this is during the first week of October. You’ll be able to resume light watering in November.
Make certain, however, that your home environment provides enough humidity for the plant — household humidity levels should be around 50%. Lack of humidity and/or overwatering may lead to the buds dropping off soon after they form.
After a month or so, the tips of the leaves should begin to grow, and buds should start to form shortly afterward. After buds have formed, it should be about four weeks before the first flowers begin to appear on your Christmas Cactus.