Christmas cactuses bloom in winter, when the days grow cool and short. While low light levels trigger flowering, fertilizing Christmas cactus at the right time and in the right way is key for getting your plant to bloom like never before. In the guide below, you’ll learn exactly how and when to fertilize Christmas cactus plants and find the best fertilizer options for providing the right nutrients for lots of spectacular flowers.
Best Fertilizer for Christmas Cactus
Christmas cactuses, and the closely related Thanksgiving and Easter cactuses, are not your standard cactus plants. Not only do these cactuses not produce spines, but they’re actually tropical plants that are native to the steamy rainforests of South America. So, it’s no wonder they have different care needs from prickly desert cacti.
While desert cactuses are commonly fertilized with a cactus or succulent fertilizer, holiday cactuses bloom best when they’re fertilized with a balanced, liquid, organic houseplant or African violet fertilizer. Adding some compost or worm castings from time to time on top of the potting soil can be helpful too. Some gardeners also recommend applying Epsom salt diluted in water throughout the growing season to meet holiday cactuses’ higher-than-average need for magnesium.
When to Fertilize Christmas Cactus
It may be tempting to fertilize Christmas cacti when you see flower buds forming on their branches in winter. But if you wait until right then to fertilize your plants, they won’t have the energy they need to bloom well. Not to mention, most houseplants can’t absorb fertilizer effectively in winter and continuing to fertilize plants late in the season can lead to root burn and other issues.
Instead, it’s best to start fertilizing Christmas cactuses in early spring—when you see the first signs of new stem growth. Continue fertilizing your plants through late spring and summer, but stop fertilizing in early fall, and don’t fertilize again until the following spring. You can use this same fertilizer schedule for any holiday cactus plant, including Easter and Thanksgiving cacti.
Fertilizing schedules and techniques will vary depending on the type of fertilizer you’re using, so it’s always wise to read fertilizer packaging closely before applying any product to your plants.
How to Fertilize Christmas Cactus
Christmas cactuses are relatively light feeders, so they usually do well with liquid organic fertilizers, but you can also feed them with fertilizer stakes or a granular fertilizer intended for flowering houseplants. If you’re using liquid fertilizer, dilute the fertilizer to half-strength with water and apply the diluted fertilizer about once every two to four weeks as part of your regular watering regimen.
After watering, drain away any extra fertilizer pooling in your plant saucer so the roots don’t sit in soggy soil. And flush the soil with rainwater or distilled water every few months to keep fertilizer salts from building up.
If desired, you can also apply a light application of worm castings or compost around your plants in spring and midsummer and feed your plants once a month with Epsom salt diluted in water. Use about 1 teaspoon of Epson salt for every 1 gallon of water and don’t apply the Epsom salt mixture during the same week that you apply liquid fertilizer.
