Holiday cacti, aka Thanksgiving cactus (Schlumbergera truncata) and Christmas cactus (S. x buckleyi ), are popular houseplants which grow (and re-bloom)for many years with good care. Christmas cactus has rounded (scalloped) stem segments while Thanksgiving cactus has 2-4 pointed teeth paired along each segment edge. The latter blooms 3-4 weeks earlier than Christmas cactus and is available in several colors. Holiday cacti are actually tropical epiphytes (like orchids) and not true cacti.

Holiday cacti bloom when exposed daily to uninterrupted 12-hour dark periods over 6-8 weeks starting in late September. A dark closet is a good place to do this. They also bloom when exposed to cool temperatures between 50 to 55 °F regardless of dark exposures.

Flower buds may drop prematurely due any of four factors: 1. over-watering, 2. low room humidity, 3. dry potting soil, and 4. insufficient light. Do not place a plant near a cold or warm draft such as a heating vent or poorly insulated window in your home.

Holiday cacti produce more blooms under bright light. Site your plants in a sunny window indoors, or beneath a shade tree in the summer garden. Leaf edges may redden or burn when exposed to excessive light.

When blooming in the fall and early winter holiday cacti are kept moderately dry and not fertilized. Water and fertilize in spring and summer when actively growing with houseplant-type fertilizer such as Miracle-Gro™, Peters®, Hollytone® or Schultz®. Follow the label directions. In March or early April holiday cacti are to encourage better branching before new spring growth begins.

Before the start of spring, repot the plant into a slightly larger container containing a well-drained sterile houseplant potting mix.  

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