Prepare now for a Christmas bloom

Christmas cactus.web
Laura Dean Bennett
Contributing Writer

The Christmas cactus has been a favorite houseplant since grandma’s day.
It’s not unusual for a single plant to be passed down from generation-to-generation because they’re long-lived and rather easy plants to grow. I have dragged them from East Coast to West Coast, from West Virginia to Florida and back again. I’ve grown treasured “slips” from relatives’ and friends’ plants, and I given many slips away from my own plants and potted slips in cute little pots to give as gifts.
Haven’t we all?
But if you really want to show them off during the holiday season, now’s the time to take a few simple steps. 
Grandma may have virtually ignored them in a spare bedroom or garage where temperatures were cool and no lights were used at night. And she always seemed to have the most amazing blooms for the holidays. But we may not have grandma’s green thumb, so let’s not take any chances here.
How do the professionals get Christmas cactus into bloom for the holiday season?
They keep them in cool greenhouses where the temperatures average 50 degrees and the plants receive between 12 and 14 hours of total darkness each day. They feed with appropriate bloom pushing fertilizer and water sparingly. So, we’re going to do that at home. 
In September and October, Christmas cactus plants need to be moved to a cool room where temperatures will remain around 50 degrees. Be sure not to expose them to freezing temperatures. It’s also very important they be kept in a room where no artificial light will be turned on at night. 
Christmas cacti should be placed in a spot where they get indirect bright light during the daylight hours but total darkness at night. This is much the same exposure you would give a poinsettia, except a Christmas poinsettia requires warm temperatures, whereas the Christmas cactus needs cool temperatures during the fall months.
This will not be the time to repot your cactus. It will flower best if it’s root-bound. 
Since the Christmas cactus is a tropical plant it usually requires watering on much the same basis as any other type of tropical plant. During the rest of the year you will have watered your Christmas cactus thoroughly and frequently and then allow about the top inch of soil to dry before watering again. However, during the fall and winter months, the plants should be watered a little more thoroughly and less frequently in order to get them to bloom. 
Christmas cacti require about 50 to 60 percent humidity. So it’s a good practice to place a glass, vase or tray of water near the plant. As the water evaporates it will provide the humidity the cactus needs. A humidity tray is another method that can be used. This is done by filling a waterproof saucer with gravel, then adding water halfway up the gravel. Place the pot on the gravel surface. 
The Christmas cactus should never be placed near a door that opens and closes to the outside. Likewise, keep it away from heating ducts, a fireplace or drafty area.
During the regular growing season – April through September, fertilize the plants with an all purpose liquid houseplant type fertilizer with a nitrogen ratio of no higher than 10 percent. (Of the three numbers on a fertilizer container, the first number is nitrogen.) But to ensure a Christmastime bloom, use a different fertilizer. In October or early November feed once with 0-10-10 liquid fertilizer. A second application of this fertilizer can be made in February. 
Once plants are in flower, they should be kept in bright, indirect light. Day temperatures of 70 degrees F and evening temperatures of 60 to 65 degrees F are considered ideal. Be sure to water thoroughly, but let plant dry slightly between waterings. It is especially important not to let soil dry too much during flowering.
But even after we get great buds, we still have to be vigilant. One of the most frustrating things that can happen is after the buds have developed, they rapidly drop off the plant. Bud drop can be caused by any one of several different conditions. Usually it’s because of over-watering, lack of humidity or insufficient light. 
After the Christmas holiday season, the Christmas cactus should be given about a 30-day rest. Again place it in a cool room and provide limited water. Don’t worry if it loses a few leaves or joints and appears weak during this rest period. We’re all a little tired after the holidays.
This is not the time to pinch, prune or shape a Christmas cactus. The best time is when the new growth begins in March or early April. Likewise, the best time for repotting a cactus is in February, March or April. But always keep in mind that the plant will flower best if it’s kept in a container where it’s root-bound, so if you want to repot into something bigger, do it early in the year.
Once flowers fade, continue to grow the plant as a houseplant. Soil should be well-drained and most container soils will work. Fertilize monthly between April and October with a complete houseplant fertilizer. Prune plants in June to encourage branching and more flowers. Just remove a few sections of each stem with your fingers or a sharp knife (this is what we call “taking a slip”). The removed pieces can be rooted in moist vermiculite or just a regular potting soil to make more plants. 
If your Christmas cactus is given proper care and is placed in the right location, it’s not unusual for it to flower several times throughout the year. 
But, first, let’s hope to get a magnificent bloom for Christmas – and lots of compliments and requests for a “slip!”

Photo by Laura Dean Bennett

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