by Sara Williams
Saskatchewan Perennial Society
Easy to care for, long-lived (40 years is not unusual) and relatively inexpensive, holiday cacti are popular flowering houseplants. They are available in a wide variety of colors, including red, rose, purple, lavender, peach, orange, cream, white and bi-colours, and their pendulous branches make them ideal for hanging baskets. Depending on their bloom period, they are variously called Thanksgiving cactus, Christmas cactus or Easter cactus.
But how did that Thanksgiving cactus find its way from Brazil to my kitchen window?
Enter Allan Cunningham
We have Allan Cunningham to thank for the introduction of the first holiday cactus to Kew Gardens and ultimately to the world. He was born in Wimbledon, Surry, England, in 1791. At the time, his father was head gardener at Wimbledon Park House. Well-educated at the Reverend John Adams Academy, a private school in Putney, Cunningham initially went on to practice law. But in 1810, at the age of 19, he began work as a botanist under Sir Joseph Banks in Kew Gardens.
On Banks’ recommendation, Cunningham accompanied James Bowie to Brazil as a Botanical Collector for Kew between 1814 and 1816. It was on this expedition that he found the first of these holiday cacti. He would spend the remainder of his life as a plant explorer and collector in Australia and New Zealand. He died of consumption in Sydney in 1839 after 25 years of plant collecting, almost all of it in Australia. He was 48 years old.
His obituary reads: “Few men have done more for botany and geography than Allan Cunningham, and his loss will be sincerely deplored by all who had the happiness to know him.”
The first of these cacti, discovered by Cunningham and brought to Europe by 1818 was Schlumbergera truncata which flowers in October and November and became known as the “Thanksgiving cactus.”
Schlumbergera russelliana, discovered in 1837 and introduced by 1839, blooms between February and April and became the “Easter cactus.”
In 1852, William Buckley, of Rollisson Nurseries in England, crossed S. truncata with S. russelliana, resulting in the plant we call the “Christmas cactus” (S. × buckleyi). By the 1860s, a substantial number of varieties in a range of colours were available. These were grown in “stoves” (Victorian heated greenhouses) and in homes, and greatly valued for their autumn and winter flowers.
From the 1950s onwards, breeders in Europe, North America, Australia and New Zealand produced new plants by crossing the species and varieties of S. truncata, S. russelliana and S. × buckleyi. The result was a wide range of flower colours which had not been previously available, including the first true yellow ‘Gold Charm’.
Today’s Holiday Cactus
In their native habitat of the coastal mountains of Brazil, they grow in shady rain forests in pockets of leaf debris in the clefts of tree branches or on rocks. With a height and spread of about 12 inches (30 cm), they are densely branching, with pendent stems consisting of many thin, flat segments, each about is 1-1.5 inches (2.5-3.8 cm) long x ¾-1 inch (2-2.5 cm) wide and with a prominent midrib. Because they lack true leaves, photosynthesis occurs within the green stem segments.
Thanksgiving cactus (Schlumbergera truncata) generally flowers for about 7 weeks around American Thanksgiving in November. Their stem segments have 2 to 4 saw-toothed serrations or projections along the margins. The pollen-bearing anthers of the flowers are yellow.
Most of the modern varieties of Schlumbergera are Thanksgiving cacti.Their flowers are held more or less horizontally, and the upper portion of the flower is shaped differently from the lower portion.
Christmas cactus (Schlumbergera x buckleyi) blooms about a month later. The stem segment margins are more rounded, and the anthers are pink to purplish-brown. The teeth on the stem segments are more symmetrical as are their flowers which hang down.
Easter cactus (Schlumbergera gaertneri) flowers primarily in the spring and sporadically throughout the year with pink or red flowers. The star-shaped flower buds form in February and flower from March through May. Easter cacti have pointed teeth with fibrous hairs or bristles in the stem joints.
Next week: Part two, Care of Holiday Cacti
Sara Williams is the author and coauthor of many books including Creating the Prairie Xeriscape, Gardening Naturally with Hugh Skinner and, with Bob Bors, the recently published Growing Fruit in Northern Gardens. She continues to give workshops on a wide range of gardening topics throughout the prairies.
This column is provided courtesy of the Saskatchewan Perennial Society (SPS; firstname.lastname@example.org ). Check our website (www.saskperennial.ca) or Facebook page (www.facebook.com/saskperennial) for a list of upcoming gardening events.