Moisture Important to Keeping Holiday Cactus in Festive Spirits

— Written By and last updated by Diane Lynch

Q: How do I get my Christmas cactus to bloom?

A: You don’t typically think of cacti blooming at Christmas time, but the Christmas cactus offers exotic flowers in many different colors during the holiday season. A Christmas cactus is also different than typical cacti because they are thorn-free.

There are actually different types of holiday cacti named for the time they bloom: Easter, Thanksgiving and Christmas. The Thanksgiving cactus typically starts blooming in late fall while Christmas cactus is around a month later. An Easter cactus starts producing flower buds in February. Thanksgiving and Christmas cactus are the most commonly seen and are often sold as “Christmas cacti” because they look so similar. To determine whether you have a Thanksgiving or Christmas kind, will depend on the edges of the leaves. Christmas cacti have smooth, round edges while Thanksgiving cacti have pointy, jagged ones.

Holiday cacti were developed from species of Schlumbergera, a tree dwelling cactus native to the tropical rainforests of Brazil. In the wild they would grow propped between tree branches or in rock crevices, absorbing nutrients from rain water and decaying leaves that get caught among the roots. As houseplants, they need to be grown in light, well drained potting soil and bright light. Holiday cacti actually bloom best when potbound, so growing them in slightly smaller containers is okay.

As for the care of holiday cacti, keeping them evenly moist is important. They do not do well in wet soils and will rot if frequently overwatered. A good rule of thumb for watering these plants is when the top inch of their potting soil appears dry and the container feels light when lifted. Add water until it begins to drain out of the bottom of the pot and allow the plant to drain for a few minutes. If your container has a saucer underneath, be sure to pour out any excess water after each watering. Frequency of watering and fertilizing will vary depending on the time of year. Plants are actively growing from spring through fall, so they should be watered more frequently and fertilized with a water soluble fertilizer every couple of weeks. Since they are tropical plants, they prefer temperatures between 60 and 80 degrees. You can place them outdoors in light shade after the chance of frost in the spring has passed. When the temperature drops in the fall, you will want to transition them back indoors, especially before the chance of frost or freezing temperatures.

The biggest problem or complaint when growing holiday cacti is trouble getting them to rebloom. Failure to rebloom can be caused by sudden change in temperatures or moisture, or exposure to light at the wrong time. These plants are considered short day plants, meaning they will only begin to form flower buds when exposed to over 13 hours of continuous darkness each night. Any light that interrupts this continuous dark period can stop flower formation. Even light from a street lamp or car headlights can stop flower formation. Around October, our nights begin to reach 13 hours. This is when you would want to put your holiday cacti in a location that stays dark all night. I often put mine in a spare bedroom where the lights are rarely turned on. As flower buds begin to form, you will see them at the tips of each branch.

Another common problem is that flower buds form but fall off before opening. If the plant dries out or is exposed to very warm or very cool temperatures (over 90 or under 50 degrees) after flowers buds form, they will often drop off or fail to open. Avoid drastic changes in temperatures and moisture to prevent flower buds from falling off before opening.

Another tip about Holiday cacti is that they are very easy to root. Collect any leaf segments that break off or cut some off and stick into a small container of potting soil. You can also put them in a small cup of water until roots form and then transfer into a container of potting soil. They will root within a few weeks. It makes a great way to grow some holiday cacti to share with family and friends during the holidays.

Learn More!
• Visit our website at https://wayne.ces.ncsu.edu/. Click on “Lawn & Garden” on left side of webpage.
• “Like” us on Facebook to receive timely garden tips, ask questions, and learn of upcoming gardening events. www.facebook.com/waynecountygardening

Upcoming Wayne County Extension Gardening Programs:
• The Beekeepers of the Neuse are gearing up for the bee school in January! The classes will begin the second Saturday in January from 9 to 12 p.m. at the Wayne County Extension Office (208 W. Chestnut St. Goldsboro). The school will be January 10, 17, 24, and 31st with February 7th being the written test for becoming a NC Certified Beekeeper. If you are interested in signing up, please contact the Wayne County Extension Office at 919-731-1520 so we can add your e-mail address and/or phone number to the list to receive more information about signing up.

NCSU & NC A&T University commit themselves to positive action to secure equal opportunity regardless of color, creed, national origin, religion, sex, age or disability. In addition, the two Universities welcome all persons without regard to sexual orientation.

Jessica Strickland
Extension Agent
Horticulture
North Carolina Cooperative Extension
Wayne County Center
P. O. Box 68
Goldsboro, NC 27533
E-Mail: jessica.strickland@waynegov.com
Phone: 919-731-1520
Fax: 919-731-1511
https://www.ces.ncsu.edu/wayne