Growing Holiday Cactus
Holiday cacti are popular seasonal plants native to Brazil. Holiday cacti are available in a wide range of flower colors including white, yellow, orange, pink, red, lavender and a few bicolor. Other characteristics which differ among cultivars are density of branching, stem texture, shape of joints, shape of flowers and time of bloom. There is much confusion about the different species which include Thanksgiving, Christmas and Easter cacti.
Holiday cacti are often distinguished from each other by their leaf margins. Christmas cacti have flat short joints, 2 to 3 rounded or scalloped teeth on leaf margins and purple anthers. Margins of the Thanksgiving cacti have 2 to 4 pointed claw-like margins and elongated blooms with yellow anthers. Grown under normal day-length, cacti bloom near the holiday suggested in their name. Growers can manipulate day-length and bring both species into bloom for the Christmas season. Easter cacti have pointed margins and bristles at the apex. They bloom primarily in the spring and sporadically throughout the year. All of these cacti have similar cultural requirements.
Flowering cacti should be kept in bright, indirect light. Too much light can cause flower color to fade. Day temperature of 70 degrees and evening temperatures of 60 to 65 degrees are ideal. Avoid over watering during flowering. Do not fertilize the plants when they are flowering.
Once the flowers drop most growers continue to grow the plant as a houseplant. Holiday cacti often become dormant for a few months after flowering. Water sparingly only using enough to keep soil lightly moist. Holiday cacti are tolerant of dry, slightly under-watered conditions but are not tolerant of water-logged soil. Start fertilizing monthly after the new growth begins and continue until two months before flowering. Plants enjoy being totally pot bound and dislike being disturbed. Repotting is recommended only once in 3 years. The potting media of choice should be well-drained with good aeration.
The secret of good flower bud production involves temperature and dark (photoperiod) control. Plants need bright light and cool temperatures. Night temperatures between 50 and 60 degrees are required. Temperatures above 90 degrees and continuous warm temperatures can cause flower buds to drop. Long nights with 13 or more hours of continuous darkness each day is required before flowering will occur. Long nights are needed for about 8 weeks.
Holiday cacti commonly drop unopened flower buds. Environmental factors such as media becoming too dry or too wet, a sudden change in temperature or light can cause the drop. An excessive number of buds can also induce the drop as can a cold draft.
Holiday cacti are excellent pot plants and make good gifts. If you receive one this holiday season, follow these tips and it can be enjoyed for years to come.