The Thanksgiving Cactus (Schlumbergera truncata) and the Christmas Cactus (Schlumbergera x buckleyi or S. bridgesii) are popular holiday houseplants, valued for their vibrant, colorful blooms that appear during the winter months. Both plants are tropical epiphytes native to the humid coastal mountains of Brazil. Because they look remarkably similar when not in bloom, these plants are frequently misidentified and often grouped generically under the name “Holiday Cactus.” Learning to distinguish between the two relies on observing distinct physical and flowering characteristics. The visual structure of the stem segments and the timing and shape of their flowers provide the clearest differences between the two species.
Segment Shape and Spines
The most dependable way to identify which plant you own is by closely examining the shape of the flattened stem segments. The Thanksgiving Cactus (Schlumbergera truncata) has segments with prominent, sharp, pointed projections along their edges. These claw-like teeth usually occur in two to four pairs on each side of the segment, giving the plant a distinctly jagged or saw-toothed appearance. This pointed structure is so characteristic that the plant is sometimes nicknamed the “Crab Cactus.”
By contrast, the true Christmas Cactus (Schlumbergera x buckleyi) exhibits a softer, more rounded morphology. Its stem segments feature gently scalloped or tear-dropped edges that lack the sharp points of its Thanksgiving counterpart. The margins look smoother and more symmetrical, presenting a subtle visual difference from the jagged edges of the Thanksgiving variety. Their shape remains constant regardless of the blooming cycle.
Bloom Schedules and Flower Differences
The timing of flowering is a key differentiator between the two holiday plants. As their common names suggest, the Thanksgiving Cactus typically initiates its blooming period first, producing flowers from late October through November. The Christmas Cactus tends to bloom later, with its flowering period beginning in late December and extending into January.
The flowers themselves also offer distinguishing features, particularly in their symmetry and how they are held. Thanksgiving Cactus flowers are notably asymmetrical, growing horizontally or slightly upward and outward from the stem segments. In contrast, the flowers of the Christmas Cactus are more symmetrical and have a distinctively pendulous habit, hanging downward from the plant. The color of the pollen-bearing anthers is also a differentiator: the Thanksgiving Cactus has bright yellow anthers, while the Christmas Cactus has pink or purplish-brown anthers.
Why They Are Often Confused
The primary reason for confusion is that the early-blooming Thanksgiving Cactus is the variety overwhelmingly sold in commercial settings during the entire holiday season. Retailers frequently label the readily available Schlumbergera truncata simply as “Christmas Cactus” or “Holiday Cactus” to meet consumer demand for a blooming plant closer to December. This widespread mislabeling has led to the Thanksgiving Cactus becoming the plant most people assume is the Christmas Cactus.
Growers can manipulate the bloom time of the Thanksgiving Cactus by adjusting light and temperature conditions, causing it to flower well into December and January, further blurring the line between the two plants. Despite the unreliable nature of the common name or the label on the pot, examining the unique shape of the stem segments remains the most reliable method for accurate identification.