Christmas Cactus and Thanksgiving Cactus are popular holiday houseplants, known for their vibrant, festive blooms. Often mistaken for one another, these tropical cacti bring a splash of color to homes when many other plants are dormant. While similar in appearance and care, understanding their distinctions helps provide optimal conditions.
Key Visual Distinctions
The main way to differentiate a Thanksgiving Cactus (Schlumbergera truncata) from a Christmas Cactus (Schlumbergera x buckleyi) is by their stem segments. The Thanksgiving Cactus features flattened stem segments with distinct, pointed, claw-like projections or “teeth” along their edges. In contrast, the Christmas Cactus typically has stem segments with more rounded, scalloped, or smooth edges, lacking the prominent points seen on its Thanksgiving counterpart. This difference in segment shape is often the most reliable visual cue.
Flower shape and orientation also offer distinguishing characteristics. Thanksgiving Cactus flowers tend to be more asymmetrical, often held at a more upright or horizontal angle, with the upper side appearing different from the lower side. Their flowers can be red, pink, orange, yellow, or white. Conversely, Christmas Cactus flowers are generally more symmetrical and have a tendency to hang downwards. The anthers, which hold pollen, can also differ; Thanksgiving Cactus typically has yellow anthers, while Christmas Cactus often has purplish-brown or pink anthers.
Blooming Schedules and Triggers
Their common names reflect their typical blooming periods, influenced by environmental cues. The Thanksgiving Cactus, Schlumbergera truncata, generally blooms earlier, with its flowering season often starting in late October and extending through November, aligning with the Thanksgiving holiday in the Northern Hemisphere.
The Christmas Cactus, Schlumbergera x buckleyi, tends to bloom later in the season. Its flowering period typically begins in December and can last through January, coinciding with the Christmas holiday. While these are general guidelines, modern cultivation practices can sometimes manipulate blooming times, causing plants to flower outside their traditional windows.
Both cacti are “short-day” plants, meaning their flowering is primarily triggered by shortened daylight hours and cooler temperatures. To initiate blooming, they generally require a period of 12 to 14 hours of uninterrupted darkness each night, combined with cooler temperatures, ideally between 55°F and 65°F (13-18°C), for several weeks.
Shared Care Principles
Despite visual and blooming differences, Christmas and Thanksgiving cacti share many fundamental care requirements, rooted in their origins as epiphytes from the tropical rainforests of southeastern Brazil. They grow on tree branches or in rock crevices, absorbing moisture and nutrients from decaying organic matter. This background dictates their shared needs for healthy growth and prolific flowering.
Both types thrive in bright, indirect light, mimicking the filtered sunlight they receive under a tree canopy. Direct, intense sunlight can scorch their delicate stem segments. Watering should be consistent but cautious; allow the top 1 to 2 inches of soil to dry out partially between waterings to prevent root rot, as they do not tolerate soggy conditions.
A well-draining potting mix is crucial for these cacti, ideally a blend formulated for succulents or cacti, or a general potting mix amended with perlite or sand to enhance drainage. They prefer moderate temperatures, typically ranging from 65-75°F (18-24°C) during active growth, and appreciate higher humidity, especially when budding and blooming. Light fertilization with a balanced liquid fertilizer is beneficial during their growing season (spring and summer). After flowering, both plants benefit from a short rest period, during which watering and fertilization should be reduced.