Indoor Plant Time in Winter Months
Re-blooming Christmas Cactus
One of the most popular houseplants, Christmas cactus is a great way to add a burst of color indoors during dreary winter months. But don’t be fooled by the generalized name—there are actually three types of holiday cactus.
“The three types, Thanksgiving (Schlumbergera truncata), with pointed “teeth” on the stems, Christmas (Schlumbergera x. buckleyi), with rounded tips, and Easter cactus (Hatiora gaertneri), are actually epiphytes. They live in trees in their native Brazil like orchids, but we grow them in pots here,” says Dr. Steve Newman, Greenhouse Crops Specialist with Colorado State University Extension.
Although they’re cacti, they don’t grow dry; water plants weekly as the top inch of soil gets dry, and provide it with half-strength fertilizer each time you water. Every third week, give it clear water instead. Avoid drafty areas for your cactus – chilly blasts aren’t good for it.
To have your cactus bloom for Thanksgiving or Christmas next year and each year thereafter, mark your calendar for September 19 as the date to begin the re-blooming process. A combination of cool temperatures and darkness is the cue these plants need to bloom, so move the cactus to a place with cool, 60-degree nights and only nine hours of sunlight daily. After approximately six weeks, Thanksgiving cactus will flower, and after two to three months, Christmas cactus blooms.
The secret to eye-popping color is reducing water to the plant after flower buds have formed, says Newman. Water weekly until after the flower buds begin to swell, then cut back on the water slightly, letting the cactus dry out between waterings. Blossom color intensifies if the plant dries once flowers start.
If the soil gets too dry, however, the flowers may drop from the plant. Get to know your cactus soil by inserting your finger in it up to the first knuckle, just before watering. Note that moisture level; as you dry down your cactus, check the soil to gauge when it’s a bit drier but not parched.
As flowers unfold, move it into the room where you want to display it, keeping it in bright, indirect light. A cool room is best; too much heat can cause flowers to fade and drop quickly, and if the leaves wrinkle, the plant is too dry or too warm. There’s no need to feed it during blossom, but after flowering, return the cactus to normal care of fertilizing at half strength and watering weekly.
Autumn Gold Landscapes, Denver, Colorado