How to get your Christmas cactus to flower

Christmas cactuses are easy to grow but are sometimes difficult to get to bloom. A medium light intensity and a soil high in organic matter are recommended. Do not allow the plant to dry out, water when the soil surface begins to feel dry. Your plant may be kept drier in fall. Any fertilizer may be used according to label directions. Cool temperatures or long nights are required to induce blooming. The plants bloom when given night temperatures near 55 degrees and day temperatures below 65 degrees.

Flowering is related to day length and night temperatures. The temperature range for flower bud development is 55 to 60 degrees for a six week period. If temperatures remain in this range they will develop buds regardless of day length. If temperatures get above that range, the plant will need 13 hours of uninterrupted darkness each night. This can be done by placing them in a completely dark room, or covering them for the recommended time, or longer, each night with a dark piece of cloth.

Or just keep the plants in total darkness like a closet till buds develop.
For holiday blooms this usually means in late September to mid October.

During flower bud formation, stop fertilizing and only water enough to keep the leaves from becoming shriveled. Once buds do form then you can keep the plant in normal light and temperatures. Keep it evenly moist and fertilize every other week with a mild fertilizer solution.

The schedule of the ideal life of a Christmas Cactus

September to October - Plant prepares to flower
Reduce length daylight hours. Keep on the dry side and cool (55 to 60 degrees F) until flower buds form. Then increase water and temperature.

November to December - Flowering
Water normally. Temperature no less than 55 degrees F.

January - Flowering

February to March - Resting
55 degrees only infrequent watering

April to May
Water thoroughly when potting mix begins to dry out.

June to August
Place outdoors in a shady spot.