Garden Guide: What is a Christmas cactus?

Most holiday plants are either challenging to keep as houseplants or pretty ugly when they aren't in bloom. That’s not the case with holiday cacti! 
These are no ordinary cacti. They don’t grow in deserts and can’t tolerate direct sunlight. They grow in rainforests and consist of three species that bloom around Thanksgiving, Christmas, or Easter. 

Not your ordinary cactus

Many gardeners accidentally kill these easy plants because the name “cactus” usually implies these plants like it dry, but these plants are rule breakers! They are true cactus, because they have photosynthetic stems instead of leaves and tiny areoles, (which are not sharp like other cactus). That’s where the similarities to their desert cousins end. 
Holiday cacti are mainly part of the Schlumbergera genus. In the forests of Central America, where these are native, you’ll find them growing in trees or even on rocks. Treat this like any other houseplant. They like fast-draining soil. Water at least 2 to 4 times a month. A bright window with indirect sunlight is the perfect home. 
Be prepared to write this plant in your inheritance, it can live for more than 100 years! 

How to get these plants to bloom again 

The blooms on these quirky plants develop when they sense changes in daylight and temperature. The easiest way to get them to bloom is to bring them outside in a shady spot during the summer. They’ll naturally start budding when the weather cools down. Sometimes when I take my holiday cactus outside in the spring, they’ll even bloom in early summer because the nights are still cool. 
I’ve broadly referred to these plants as “Holiday Cactus” in this article because there are three different species (and hundreds of flower colors and shapes to choose from). 
The most common holiday cactus is the Thanksgiving cactus (Schlumbergera truncata) They’re sold as Christmas Cactus! Most people do their Christmas decorating around Thanksgiving time so stores usually stock up with this type of holiday cactus. Pointy pads (they aren’t sharp!) are the easiest way to identify these from other holiday cacti. And don't worry about the flowers fading before Christmas. When they’re happy, they’ll last for a month or more. 
Christmas cactus (Schlumbergera bridgesti) is rare in stores today but was much more common decades ago. If you inherited a holiday cactus from grandma, it is more likely to be one of these! The pads are rounded, and the flowers are tube-shaped. They typically bloom just after Thanksgiving cactus. They have a very droopy growing habit that makes them perfect for a hanging basket! 
Then there’s the Easter Cactus (Rhipsalidopsis gaertneri). These have recently been reclassified into a different genus than Thanksgiving and Christmas cactus. It makes sense because the star-shaped flowers are pretty unique. Fortunately, the growing requirements are the same! These blooms develop after the shortest and coolest days pass, right in time for Easter!

What you need to know 

  • These plants are true cactus, but not desert cactus 
  • Keep them away from hot sunlight, and water generously 
  • They bloom under stress 
  • Cooler, shorter days, and a little less water than usual will trigger blooms. 
  • They can live for over 100 years
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