Master Gardner: A little TLC for Christmas cacti
If you’ve enjoyed the colorful blooms of Christmas cacti, you’ll want to take good care of the plants. Keep them in bright spots away from drafts (e.g., heat vents, fireplaces, frequently opened doors). Water well when the soil surface begins to feel dry.
It’s not essential to fertilize Christmas cacti, but you may wish to do so while they’re actively growing. Use a general blooming houseplant food and follow label directions.
Even after blooming, plants should stay in sunny spots indoors. If you wish to move plants outside in the summer, choose a shady or semi-shady area as leaves can burn from direct sunlight.
Pruning Christmas cacti after blooming will encourage the plants to branch out. Remove a few sections of each stem by pinching or cutting with a sharp knife. If you wish, you can propagate new plants by rooting the sections in moist vermiculite.
If your plants are drying out rapidly, it may be time to repot. Select a slightly larger pot and provide well-draining soil. You may use a commercial potting mix for succulents or make your own by combining two parts plain potting soil with one part vermiculite.
Next fall, start to provide your Christmas cacti with long, dark nights – a full twelve hours of darkness. Once buds form, the plants can be placed in ordinary room conditions. Alternatively, keep plants at 50-55 degrees until buds form. While using one of these approaches is ideal, many gardeners do find plenty of blooms on their Christmas cacti without doing anything special.
If you have a poinsettia, the care is not dramatically different. Keep the plant in bright light and preferably at temperatures below 70 degrees. Check the soil often and water thoroughly when it is dry. That means watering until the excess runs from the drainage hole. If you are using a saucer, dump the excess water before repositioning the plant.