SCHLUMBERGERA HYBRIDS (Holiday cactus)
(Holiday cactus, Christmas cactus, Thanksgiving cactus)
Schlumbergeras are native to the tropical forests of South America, where they grow on trees.
Their stems are unusual and the blossoms are beautiful and timely. The stems are spineless, but scalloped, and bear tubular flowers in a wide range of colors at Christmas time. S. truncata (Thanksgiving cactus) flowers earlier in winter. Its stem joints are longer and narrower than later- blooming schlumbergeras. The 3-inch long flowers, borne at the ends of the stems, are shades of white and red.
Schlumbergeras require a rich, porous soil. Keep the soil moist but not soggy, and fertilize weekly when the plants are growing. They do well in front of a vool, bright window. During the summer you can move them outdoors into partial shade. Budding is brought on by the short days of October and November or by a cold shock. To promote flowering, place plants outdoors for a time during the fall. After plants flower, keep them drier and withhold fertilizer.
Light: Place in a bright but indirectly lit south, east, or west window.
Water: Keep very moist during growth and flowering; at other times, allow to dry between waterings.
Humidity: Average indoor humidity levels.
Temperatures: To set flower buds, 40° to 45° F at night, 60° to 65° F during the day. At other times 50° to 55° F at night, 65° to 70° F during the day.
Fertilization: Fertilize only when the plant is growing actively or flowering.
Propagation: Take cuttings from recently matured stems or shoots when the plant is not in flower.
Grooming: Prune after flowering if needed.
Repotting: Repot infrequently, into a humus-rich soil.
Problems: Dry soil or a high level of soluble salts may damage roots, causing dieback.