Schlumbergera is a houseplant that cheers up many a holiday home. Common names for members of this genus of cactus include Christmas cactus, Thanksgiving cactus, holiday cactus (which actually blooms in spring) or crab cactus. They bloom in pink, white, yellow, orange and red, and are a relatively easy-care houseplant.
Schlumbergera is a form of jungle cactus that typically sends up blooms toward the end of the year. In its natural environment, the cactus lives in trees or on rocks, but most northern gardeners know it as a plant that adapts very well to life indoors.They can tolerate some dryness, but unlike desert cacti cannot be left dry for weeks on end. These plants are natives of the rainforests of Brazil, so give them water when the potting mix is dry to the touch. Make sure the potting soil you put them in has very good drainage, too, and don’t be in a hurry to re-pot your Christmas or Thanksgiving cactus. They like to be slightly pot-bound. It’s recommended that the plants be fertilized monthly from April to October. You can put your cactus outdoors in summer, preferably in a somewhat shady spot. Here’s a good tip sheet on caring for Thanksgiving and Christmas cacti.
Blooming is a response to lengthening periods of darkness. According to Clemson University, the members of this group of cacti require 14 hours of darkness to initiate bloom. Brightness from street lights or indoor lights can cause plants to drop their blossoms or fail to bloom. Turn off the lights, if you want the blooms! When in bloom, keep plants in a sunny window and don’t let the soil dry out. When blooming is over, the cacti are an attractive houseplant.
How can you tell if you have a Thanksgiving or Christmas cactus? Look at the leaves. If the leaves have pointy tips, like those in the photo above, it’s a Thanksgiving cactus. If the tips of the leaves are rounded, it’s a Christmas cactus. (Check out this blog post for images of Christmas cactus leaves.)
Is your Thanksgiving or Christmas cactus ready to bloom?