Jennifer Schultz Nelson
Extension Educator, Horticulture
The Christmas Cactus was one of the first flowering houseplants I bought with my hard-earned babysitting money in high school. I remember my mom remarking that she had heard you could never get them to re-bloom. Being stubborn, I was determined to prove her wrong. After that first spectacular year of blooms, I pampered that plant like no other. After all, the Christmas Cactus is not your typical cactus.
The Christmas Cactus' native environment is tropical, not desert like the name "cactus" suggests. So they can tolerate more water than you might expect, and can store some in their succulent leaves. The Thanksgiving and Easter Cacti are also tropical. Unlike their desert relatives, these cacti cannot tolerate intense full sun. They are used to growing in the lush understory of tropical forests.
As much as I pampered that plant the first year, I wasn't rewarded with new blooms the following year as I had hoped. I did have tons of new growth on the plant, probably due to my overzealous use of fertilizer that I mistakenly thought would trigger flowering. It did eventually re-bloom, but only a couple of blooms at the most. It wasn't until graduate school (yes, it was still the same plant!) that I stumbled on the secret that convinced my plant to produce tons of flowers.
The fall semester had started, with its normal crazy rush of research and classes. The weather turned cooler, and I was too busy to bring my houseplants, including the Christmas Cactus, in from their summer outdoors. When I finally brought the plants in, I noticed the Christmas Cactus was covered in flower buds. Not just a few, but the end of every arching branch had one or even two buds.
It turns out that the cooler and longer nights of early fall are the environmental trigger for flower development in the Christmas Cactus. What a happy discovery!
Check out more University of Illinois Extension information about Christmas Cactus at: http://www.urbanext.uiuc.edu/trees/flowersgreen.html.