Growing up my mom always called her Christmas cactus a Thanksgiving cactus because it would be in full flower by the end of November. Being the good son, I never questioned Mom or try to correct her. Twenty something years and a few advance degrees later, Mom was right. The popular plant that’s now arriving in garden centers for the holiday season, Schlumbergera truncata is actually called the false Christmas cactus or Thanksgiving cactus.
Yes you have been lied to.
To get over this deception we need to dive deeper into the torrid love affair with the Christmas cactus. Turning the calendar back 177 years to 1840’s England we find William Buckley, a dedicated horticulturist, and his experiment of a cross between two species of Schlumbergera. He crossed S. truncata with S. russelliana and created the hybrid S. x buckleyi that was christened the true Christmas cactus. As you are sitting at home reading this you’ll be tempted to do some quick internet searches and you may come across some old literature that reference this cross erroneously as S. bridgesii which is one more layer of deceit. You will, no doubt, find some older literature that use Zygocactus as the genus.
The plot thickens.
Now that you are staring at your false Christmas cactus dismayed and wondering where to find the real Christmas cactus you need to know a few more things. It is hard to weed out the imposters and you need to know a little bit of botany. The “leaves” of the Schlumbergera are actually flattened stems called cladophyll (phylloclades by some botanist). The false Christmas cactus will have stems that have an open branch habit and the margins will have soft points or teeth. Note: these points are not spines just deeply lobed portion of the stem. Flowers of the false Christmas cactus will be bright and cheery in shades of pink, white, peach, and salmon. They will be held at the end of the stems pointing slightly upwards and lasting for about 5 sometimes 7 days. The flowers will also appear a little flat or horizontal. The true Christmas cactus will have stems that dramatically arch downwards with a closed habit. The margins of the stems will be rounded with small visible points or nubs. True Christmas cactus flowers will be more rounded than the imposter and will follow the direction of the stem and point down. Colors will be carmine, pink and reds.
As you set out on your quest to locate the true Christmas cactus you may run across a close cousin of Schlumbergera called the Easter cactus Rhipsalidopsis gaeteneri. You’ll be happy to know that they are not of commercial importance in the garden retail industry and rarely offered. Also, as the name implies they flower in the spring. But if you happen to run across one . . . what’s one more plant, right?
Finally I am sure you’ve read through this article and skimmed over the genus name because you, like myself, can’t pronounce it (shlum-BER-ger-uh) and I doubt that did much to help. A quick bit of information Schlumbergera are a group of true cacti belonging to the Cactaceae family that thrive in conditions that we normally do not associate with cacti. They live deep within the tropical rainforest of South America and live on trees like orchids.
Good luck on your adventure and let me know if you find a true Christmas cactus to add to your collection.