The Christmas cactus is a beautiful indoor plant. It is easy to care for, long living and will bloom annually with the proper conditions. It is a member of the 'Zygocactus' family which is a forest cactus, and is different from the desert cactus. It is an epiphyte, and in its natural habitat, in the forests of South America, they can be found growing in the nooks and forks of trees, where they get lots of bright, indirect light and a high humidity.
To grow the Christmas cactus successfully in the home you want to give the Christmas cactus the same conditions that they have in nature. Place the plant near a south facing window during the winter, and an east or west window in the spring and summer when the sun is hot. Too much sun will harm the plant and cause the leaves to burn. Christmas cactus do well in homes as they enjoy temperatures of 18-21 Celsius. Humidity is also important, so if the humidity is low in the home, place the plant on a pebble tray. A pebble tray is a tray that is at least 5 cm larger then the pot size of the plant. Fill it with rocks/pebbles and then add enough water to the tray so that the water is slightly lower then the top layer of pebbles. Place the plant on the pebble tray and as the water evaporates around the plant it raises the humidity, creating a micro climate. A forest cactus is watered different then a desert cactus. When in bloom it should be kept slightly moist, but not wet. When the top layer of soil feels dry to the touch, give the plant a thorough watering, draining out any excess water after a few minutes, and then don't water again until the soil is slightly dry. Christmas Cactus can be little finicky when they are in bloom as they do not like change. Do not place them anywhere near a heating vent, draft or outside door where the temperature can change quickly. Also a change in humidity, light, or moisture can cause the plant to drop flowers and buds.
After the plant has finished blooming it should be given a rest, by placing it in a cooler room, and cut back on the water. Around March it can be pruned back to keep its size as well as encourage branching. More branches equals more flowers! This is also when you can take cuttings from the plant. Snip of a section that has 2-3 segments and allow it to air dry for several hours before placing half of the first section into the soil. Do not give it very much water. The cutting will slightly wilt but it should root in 4-6 weeks, after which it is treated as the mother plant. Over the spring/summer months treat the Christmas cactus as you would any other tropical plant. Christmas Cactus prefer to be slightly root bound if you want them to flower again. It can be re-potted into a pot one size larger then the container it is currently in. When transplanting, use a good quality, indoor potting soil that has good drainage.
To get a Christmas Cactus to bloom again the plant needs to be prepared in the fall. It is thermo-photoperiodic, so needs the proper conditions to bloom. Give it 12 hours of uninterrupted light every night for 6-8 weeks. Also place it in a slightly cooler room and cut back on the water. The tips of the plant will begin to grow, then darken as the new buds form. When the buds have formed, the Christmas Cactus is then placed in an area of the home where it can be enjoyed.
