EDDIE SEAGLE: Holiday cacti add color to celebrations

“Thanksgiving is a time when the world gets to see just how blessed and how workable the Christian system is. The emphasis is not on giving or buying, but on being thankful and expressing that appreciation to God and to one another.”

— John Clayton

During the holidays, certain flowering plants will often be seen that are members of the cactus family and appear to look alike. These holiday cacti provide awesome seasonal appeal. Such cacti include the Thanksgiving cactus (Schlumbergera truncata), Christmas cactus (Schlumbergera bridgesii), and the Easter cactus (Rhipsalidopsis gaetneri or Hatiora gaetneri).

The Schlumbergera species are native to the tropical forests of Brazil while the Rhipsalidopsis species are native to the natural forests of Brazil. Schlumbergera truncata grows in the rain forest at an altitude between 3,000 and 5,000 feet, growing on decaying organic debris trapped among tree branches or in rocky crevices in shaded areas on the ground. Schlumbergera bridgesii grows at higher mountain altitudes in the cooler, dryer wooded areas.

These three species of cactus are members of the group of cacti called the leaf cacti and their plant bodies are flattened and the leaves are actually stems. The flowers develop from notches in these stems or from the tips. These fuchsia-like flowers can last several weeks. They are usually pink, but modern hybrids include white, red, yellow, and purple varieties.

Flower bud initiation responds to cool temperatures and shortened day lengths. The Thanksgiving and Christmas cactus should be left outdoors, away from artificial light until night temperatures drop into the 40s. (Our current weather has at times dropped into the 20s). At this time, they do best at temperatures between 50 and 65 degrees.

One difference between the Christmas, Thanksgiving, and Easter cacti is the time of bloom. As their common names suggest, a Thanksgiving cactus can bloom in late fall (about one month before the Christmas cactus). The Easter cactus starts producing flower buds in February. Regardless of type, there are steps to follow to ensure bloom.

Bring these holiday cacti inside and place them in a cool area, keeping them away from all light between the hours of 5 p.m. and 8 a.m., and water weekly. Avoid heating vents that can cause temperature fluctuations. The plants should come into flower sometime in late November/December through January. If you want them to bloom sooner, start the cool temp/short day treatment earlier.

The Easter cactus requires a dry period and very little water is required for flower bud initiation from October through November. The Easter cactus should also be placed in the same cool area under shorter light periods at this time. In December, raise the temperature to about 65 degrees and water sparingly. Expect flowering around March for the Easter cactus.

Regardless of which type of cactus you have, avoid high temperatures and heat fluctuations when the plant is flowering. Lack of flowering is directly related to the cool temperature and short day treatment. The Easter cactus is a bit different since it is not a tropical plant and requires a dry period.

Schlumbergera truncate is from the mountains of Brazil (not the desert) where it grows like the orchid in the crotches of trees. From late October through November, this cactus puts on a magnificent color display with multiple fuchsia-like flowers. These cacti are available in purple, pink, red, yellow, or white. Any purchases should be made in early November while the plants are in bloom (to see actual flower color).

Thanksgiving cactus (truncate) prefers a humus-rich and well-drained soil, including two-parts peat and one-part perlite. Provide them sufficient attention during warm-weather months and water every other day. Also, add an all-purpose fertilizer or plant food (150-200 ppm 20-10-20 or 15-16-17 per month), Epsom salts for magnesium (8 ounces per /100 gallons per month) and iron (Sequestrene 330, 4-6 ounces per 100 gallons). Stop all fertilization applications one month before the start of short days for flowering.

Grow them in full light during the fall and winter but provide some shade during the summer. Marginal chlorosis is common on such plants that are grown under high-light, high-temperature conditions in the summer. Cool temperatures and weekly water will insure a magnificent flowering period that may last from four to six weeks. After flowering stops, decrease water and set the cacti in full sun until warm weather (at which time, return them to shaded areas in the great outdoors).

Another difference in these cacti is the Thanksgiving cactus (truncata) has two or three jagged points on every leaf segment, and its flowering time (under normal circumstances) is from late October through November. The Christmas cactus (bridgesii) has smooth (not jagged) leaf segments, and typically flowers in January or February. These flowers are smaller and more pendulous than the truncata. And, the Easter cactus has bristles on edges of leaf segments.

Most of the cacti grown commercially are the Thanksgiving cactus. There are many instances of mislabeling found among the stores where the Thanksgiving cactus may be labeled as the Christmas cactus. You may think you have a Christmas cactus, but determine through inspection of leaf characteristics that it is a Thanksgiving cactus. However, this is no real problem since timing of bloom is so close together.

The flower colors vary among cultivars including red, orange, magenta, lavender, and white. Other characteristics which vary among cultivars include branching density, uprightness, phylloclade shape, flower shape, and flowering time. Many commercial cultivars are the result of crosses between Schlumbergera truncata and Schlumbergera bridgesii.

Thanksgiving cactus cultivars include Christmas Charm (purple), Christmas Magic (purple), Gold Charm (yellow), Kris Kringle (wine red), Lavender Doll (lavender), Peach Parfait (peach), Amethyst (rose), and Snowflake (white). Also, Red Radiance (blood red), Twilight Tangerine (orange),White Christmas (white), Maria (carmine), Snowfire (white), Sonja (rose pink), Lavender Lady (rose pink), Weiss (white), Red Beauty (red), Sabrina (purple), Majestic (purple), Christmas Cheer (brick red), Koeninger (brick red), Norris (blood red), and Margaret (carmine).

Their disease problems include Fusarium oxysporum and fungus gnats, Fusarium oxysporum (basal stem rot, root rot), Pythium aphanidermatum (basal stem rot, root rot), Rhizoctonia solani (stem rot), and Erwinia carotovora subsp. carotovora (blackish, wet bacterial blight). Avoid excess watering to minimize these root rot problems. The insect problems may include caterpillars, fungus gnat larvae, mealybugs, red spider mites, and soft brown scale. Keep a close eye on any such activity and respond accordingly.

As you plan your colors for the season with the holiday cacti, continue to enjoy the fall color and cooler weather. Think in terms of sustainability, stewardship, low maintenance, and curb appeal. Also, take the necessary measures to protect your four-legged friends and family (pets) — do not leave them out at night in the colder temperatures as the month passes forward. And, as always, remember to feed and water the birds! Be ever thankful for your blessings. Happy Thanksgiving to all!

“Come, let us sing for joy to the Lord; let us shout aloud to the Rock of our salvation. Let us come before him with thanksgiving and extol him with music and song.” Psalm 95:1-2.

Eddie Seagle is a sustainability associate, Golf Environment Organization (Scotland); agronomist and horticulturalist, CSI: Seagle (Consulting Services International); professor emeritus and honorary alumnus, Abraham Baldwin Agricultural College, and associate editor of The Golf Course, International Journal of Golf Science. Email [email protected].