You can make Christmas cactus bloom at Christmas or in Holiday season if you follow these tips. You’ll need to follow the process for at least 6 weeks to make it bloom at time.
To force it to flower, tuck your Christmas cactus indoors. Ideally, it should be kept at a temperature around 60 F and make sure it does not go up or down too much, until the first flower buds appear. During this period, the Christmas cactus needs total darkness of 15 hours and 9 hours of bright indirect light. Why so? It is a short day plant and it blooms in such conditions. Make sure that location in which you are placing christmas cactus is fulfilling both light and temperature requirements. Also make sure that is does get complete darkness for at least 14 hours, which means not even smallest lamp or source of light reach it during this period.
Keep the plant slightly thirsty. Water it sparingly until the appearance of the first flower buds: Soil must be dry between watering spells but not too much otherwise forming buds will drop.
After it has formed buds, water it regularly to promote more blooms, also make sure not to overwater as it can also cause bud drop.
Christmas cactus require about 50 to 60 percent humidity. Use the humidifier to raise the humidity in the room. If you don’t have a humidifier place a tray of water next to it. A humidity tray is good method of providing the humidity the Christmas cactus requires. This is done by filling a waterproof saucer with gravel, then adding water halfway up the gravel. Place the pot on the gravel surface.
4. Do not move
Remember the buds and flowers of this plant are very fragile, so it is better not to move the plant here and there.
Wait until the end of flowering period, before you start pruning.
Set in a large pot, the Christmas cactus has tendency to bloom less often. It is therefore recommended to keep the plant slightly root bound. Repot it in every 3 year or so. Choose a slightly larger pot than the previous one.