Aside from Christmas trees, the best-selling Christmas plants in this growing zone (5b) are in order of popularity: poinsettia, amaryllis, Christmas cactus, cyclamen and azalea. There have been recent articles about how to care for live Christmas trees, poinsettias and other indoor Christmas plants but the care of the Christmas cactus has been a mystery to me all these years.
I have been given cacti that bloomed at Thanksgiving and, once, one that obstinately refused to bloom until Easter when it burst open with beautiful star-shaped pink blooms. I was sure I had done something wrong until I learned that there are three major types of holiday “cactus” and Christmas cactus is only one of them. They appear similar to their desert cousins, but these are not desert plants but actually grow in the tropical rainforest and cling to trees or rocks. They have aerial roots that help them cling to those plants but are epiphytes instead of parasites, since they get their nourishment from the air, leaves or humus and not from a host plant.
A Christmas cactus (Schlumberga bridgesii) usually has slightly rounded leaf segments, whereas Thanksgiving cactus leaf segments have sharper points. Additionally a cactus that is intended to bloom at Easter usually has soft bristles at the edges of its leaf segments. Its botanical name is Hatiora gaertneri and properly cared for will usually show buds in the early spring and bloom in late March or April.
If you are the lucky recipient of a holiday cactus, benign neglect should be your watchword. In other words, do not over-water. Unless your home is extraordinarily dry, a once a week soaking when the top inch of the potting soil is dry should suffice. Cacti like sunny south windows in the blooming season, and like poinsettias and cyclamen dislike drafts and sudden changes in temperature. Seventy- two degrees in the daytime and mid sixties at night is ideal. These plants can be moved outdoors in late spring or early summer and brought inside again in late August or September. In order to coax them to re-bloom, they will need 12 to 14 hours of darkness each day starting in late summer or early fall.
Christmas cactus is easy to propagate and long-lived if properly cared for. Healthy green leaf segments can be rooted in damp potting soil or even in water. A gardener I know has a huge Christmas cactus that he says belonged to his grandmother and has been in the family for three generations. I had a root cutting of that plant at one time, but I seem to neglect houseplants in the winter. That one made it outside but was done in by Alphie the squirrel, or so I said.
Enjoy your colorful houseplants, Merry Christmas and Happy Hanukkah too.
If you have other questions about your garden or landscape, feel free to contact a Master Gardener volunteer at the University of Illinois Extension office in Charleston at 217-345-7034. You can also check out the many horticulture webpages at the U of I Extension’s website by visiting http://web.extension.illinois.edu/ccdms/ . And be sure to like the Master Gardeners’ Facebook page, at www.facebook.com/ColesCountyMasterGardeners.