#YouShouldGrowThis: Christmas cactus loves a cold house

If you have a Christmas cactus that refuses to bloom, it might be getting too long of a day! Christmas cacti (Schlumbergera) are very sensitive to lengthening and shortening hours of daylight. They come from the high coastal mountains of southeastern Brazil and are used to warm, humid days and cold nights. 

If yours is in a room where the lights are on until 9 p.m. when the day length should be shortening, your cactus won't know that it's Christmastime. Obviously, you want your Christmas cactus to be aware of Christmas. That's kind of the point of keeping them. Decorations won't do it. Garlands and Christmas baking mean nothing to them. They need to know that days are shortening in order to develop flower buds! 

How to make them bloom 

Christmas cactus are fine houseplants, but they need to be kept slightly moist at all times and don't like to dry out. They are best kept in bright but indirect light. They also do very well if placed outdoors in a shady spot for the summer. Usually by the time you bring them indoors in fall they are already starting to produce buds. Once they start to bud, they should be given a shot of high phosphorus fertilizer at about quarter strength every time they are watered until flowering finishes. 

Christmas cactus adore people who turn the thermostat down at night.- Lyndon Penner

They should also not be moved (they tend to drop buds) and there should be at least five degrees difference between day and nighttime temperatures. Christmas cacti adore people who turn down the thermostat at night. Another reason they sometimes refuse to flower is because it's too warm and dry in our homes. They like humidity and cooler temperatures. They will sometimes flower several weeks longer if the house is on the cooler side. They do best with cramped roots and sharp drainage.

Christmas cactus or holiday plant?

It should also be noted that Christmas cacti are non-denominational and aren't especially concerned or judgmental about what faith you choose to belong to. If you don't celebrate Christmas, you could also call it a Hanukkah cactus. Or a solstice cactus, if you are a pagan. If you are an atheist, you might wish to simply call it a cactus. Regardless of your religious aspirations, these are lovely winter blooming plants. They happily flower for Buddhists, Catholics, Jews, Hindus, Muslims, etc. without any commentary on how you choose to live your life. They are extremely inclusive plants and should thus be welcomed into our homes.