During the shortest days of the year, you can count on a Christmas cactus to brighten things up with its colorful flowers right around the holidays—except sometimes it seems to bloom about a month too early. What gives? If your plant seems to be jumping the gun, it's likely not a Christmas cactus at all, but a Thanksgiving cactus. They look very similar, but there are a few key characteristics that can clear things up about your plant's true identity.
Closely Related, Yet Different Cacti
Christmas cacti and Thanksgiving cacti belong to the same botanical genus, Schlumbergera, meaning they’re closely related. It’s easy for even the well-trained eye to mistake them for the same plant. Both grow wild in the mountains of southeastern Brazil, so they prefer things on the cool and shady side unlike the cacti found in desert habitats. This is partly why they make such great houseplants.
They are also beautiful, especially when in bloom. These plants feature pink, red, white, or yellow flowers on their flattened, spineless, segmented green stems (they technically don't have leaves). Though these cacti have similar-looking flowers and stems, each of these features offers clues to help you distinguish them from one another.
How to Tell Holiday Cacti Apart
Thanksgiving cactus (Schlumbergera truncata) was once commonly called the “crab claw cactus” or “crab cactus" before it started being marketed around Turkey Day. You can identify it by the pointy “teeth” on the sides of each stem segment. These teeth are soft, not sharp, and can vary in size, but are almost always visible on the plant to some degree.
Another way to tell which sort of cactus you have is to look at the flowers, which can bloom anytime in the fall. Sticking out from each blossom, the cluster of long, thin anthers will be tipped with pollen. If the color of the pollen is yellow, you more than likely have a Thanksgiving cactus.
What we call a Christmas cactus, on the other hand, comes from a species called Schlumbergera russelliana with some S. truncata mixed in. It has more rounded stem segments that lack pointed teeth. Its flowers usually have pink pollen. And as its name implies, it also tends to flower later than a Thanksgiving cactus.
Many New Varieties
When figuring out which one of these cacti you have growing in your house, consider the age of your plant for some hints. In recent years, all sorts of new varieties have been produced with characteristics that blur the differences between the two species. These are what you're more likely to find for sale nowadays, instead of the original species-type plants. So if your plant is a young one from a garden center or grocery store, chances are it's a major mishmash between Christmas and Thanksgiving cacti, and maybe a few other related species.
But if Grandma gave you a cutting off that 50-year-old plant growing on her kitchen counter, you might actually have a straight-up Thanksgiving or Christmas cactus with nothing else mixed in. It's also possible it could be a plant called Hatiora gaertneri, which is yet another look-alike that's commonly known as the Easter cactus because it typically blooms in spring.
Whether you have a Thanksgiving cactus or a Christmas cactus or something with a blended pedigree, you will enjoy these plants for what they are: easy-to-grow houseplants that often grace the holidays with their lovely flowers. Plus they can be passed down from generation to generation or shared with friends from a simple stem cutting.