In the Garden:
Western Mountains and High Plains
This Thanksgiving cactus is ahead of the holiday and blooming for Halloween instead.
Holiday Cacti are Easy to Grow
I'm not much of a houseplant person, but I do like to grow a few in my home. A busy schedule keeps me from fussing about special care and temperature regimes, so I choose houseplants that can survive on neglect. Recently, I was especially pleased when an orange-flowering cactus came into bloom at Halloween. No, it's not the spiny type of cactus you might be imagining; rather, it's a holiday cactus -- the kind with flattened, fleshy stems.
Holiday cacti are a group of plants in the genus Schlumbergera. One type that is particularly easy to grow is the Thanksgiving cactus (S. truncata). Like other Schlumbergeras, this is a true cactus, but it lacks the spines and the rounded, chubby body normally associated with members of the cactus family. Instead, it produces segmented, branching stems composed of flattened, leaflike sections called cladophylls, each edged with long, serrated teeth. The very showy, multi-petaled flowers can be found in shades of red, pink, rose, white, yellow, and orange. Blooms will appear from late October until well after Christmas.
The Thanksgiving cactus originates from tropical southern Brazil, where it inhabits the tree tops. The plants anchor themselves on the branches and trunks of trees, as well as on rock faces, in the damp, misty forests. These cacti obtain their nourishment from leaf mold and other organic debris that accumulates in the crevices of the host plant or rock where it is attached.
Considering the limited "soil" in its natural growing environment, it makes sense to grow the plants in relatively small containers and allow them to become somewhat pot bound. At least I've found them to respond better and bloom more profusely when grown this way.
One of the secrets to get a holiday cactus to bloom truly is neglect. I keep the plant in a brightly lit area and water only when the soil has started to dry out. It's lucky if it gets water once a week. The location near the window is somewhat cool at night and this encourages the plant to set bud earlier than it would in a warmer location. And the room gets no light after the sun sets in the evening, giving it a long night of uninterrupted darkness.
Like poinsettias, this plant is triggered to bloom by both temperature and day length. The shorter days of fall will initiate the flowering cycle. If the temperature is lower than 60 degrees F. , plants will set bud regardless of the length of the day or night. With more moderate temperatures, the plants will show a classic short-day response.
If you're having trouble getting your Thanksgiving cactus to bloom, consider where it is growing. It may have to be moved to a location where there is complete darkness after sunset. Otherwise, artificial lighting at night -- even a streetlight shining in a window -- will delay its blooming.
The common name Thanksgiving cactus has limited meaning to the rest of the world. In Europe, it is called the "crab cactus." And it's relative, the Christmas cactus, blooms in April and May its native habitat in Brazil, rendering it's common name meaningless there. April and May are the normal autumn season of the Southern Hemisphere.
Care to share your gardening thoughts, insights, triumphs, or disappointments with your fellow gardening enthusiasts? Join the lively discussions on our FaceBook page and receive free daily tips!