9 Reasons There Are No Buds on Your Christmas Cactus This Year
The winter holidays are around the corner and your Christmas cactus isn’t blooming like it should. There are several potential reasons your Christmas cactus failed to bloom this year. Houseplant expert Liessa Bowen walks through some of these common problems and what you can do to correct them.
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Christmas cactus plants make easy and forgiving houseplants, adapting easily to indoor conditions. They are also exceptionally long-lived and can provide greenery and reliable flowering for a lifetime, provided they are well cared for.
When troubleshooting blooming problems, such as a Christmas cactus with no buds, it’s good to start with a basic understanding of what these plants are and what they aren’t. They are technically cacti but they don’t follow typical cactus stereotypes. First, they don’t have sharp spines. Second, they don’t grow in the middle of a hot, dry, sunny desert.
Christmas cactus and Thanksgiving cactus are both members of the genus Schlumbergera. They are native to the humid, cool, high-elevation rainforests of Brazil. These plants are also epiphytes, meaning that they don’t grow in the ground but rather on other trees and shrubs, or they make their home nestled in the cracks of large rocks.
As a forest plant, they don’t grow in direct sunlight but rather in dappled or diluted light. They are adapted to more frequent rainfalls than desert cacti but still don’t like wet feet. The rainforests where they naturally grow are much cooler and more humid than where most hot, arid, desert species grow. When you understand their natural habitat, you’ll better appreciate how to care for these beautiful houseplants.
So why does a Christmas cactus produce flower buds some years and not others? Let’s check out some of the many reasons your plant might not be happy and what you can do about it.
Wrong Season
It may seem obvious, but it’s worth mentioning. Before you panic about your Christmas cactus not producing floral buds, make sure you’re expecting it to bloom during the appropriate season. Christmas cactus bloom around Christmas time, and Thanksgiving cactus bloom around Thanksgiving.
If it’s any other season, you simply won’t see any buds or other signs of blooming on your plants. If you have one that’s blooming in the springtime, it’s probably actually an Easter cactus—a very similar-looking plant—that blooms in early spring.
Too Much Light
Christmas cacti are triggered to bloom by a combination of temperature and day length. If this plant doesn’t receive the correct cues, it doesn’t begin a bloom cycle. Holiday cacti need at least 12 to 14 hours of darkness each night if they are going to bloom that season. There are a couple of common reasons why your plants might be getting too much light.
Nights Aren’t Dark Enough
Are your plants in a location where they are exposed to lights at night? When your cactus is exposed to your indoor household lights, the natural cycle of light and dark is disrupted. It’s best to keep your holiday cactus in a location that is well-lit during the day and dark at night.
If your plant is on the kitchen window sill and you turn on your kitchen lights at night, the plant gets confused about whether it’s day or night. Look for lights coming in from outside as well. If the streetlight shines in your window at night, close the blinds or move your cactus to a darker window.
Need help keeping your cacti dark? One way to set them on a light-dark schedule is to put them in a dark closet or dark room at night or cover them with a box at night. The challenge here is to be consistent and don’t forget your plants are tucked away in the dark. You’ll still need to uncover them to get their daytime light.
Grow Light Schedule Needs Adjusting
Are your plants under a grow light? It may be tempting to set your grow light on a timer and forget about it, keeping the same schedule all year round. If a Christmas cactus gets the same long light exposure every day of the year, this is counterproductive to its flowering schedule and it may not produce buds. Shorten the grow light schedule to better match the natural shortening of days.
You don’t have to perfectly match your local sunrise and sunset schedule, but adjusting the grow lights to a shorter light schedule can be a big help. In late September and October, switch your grow light to a shorter light exposure followed by at least 12 hours of darkness each night. Keep the light schedule fairly consistent, and use an automatic timer if you can.
These plants are very sensitive to light, so even a few days of accidental nighttime light exposure can reset your cactus and cause it to drop buds. Make sure the grow light plants are in a place where it stays dark at night, including general room lights and other ambient lighting.
Temperature is Too Warm
Christmas and Thanksgiving cacti need a period of cooler temperatures to bloom well. Along with longer nights, these plants also expect the temperature to drop. Ideally, the fall nighttime temperature should be between 55 and 65°F (13-18°C), with daytimes a little warmer, starting in late September.
Fortunately, you don’t need to welcome fall by cranking your air conditioner to a cooler setting. Just place your plants in a cool window and keep them away from heat sources like furnaces, fireplaces, radiators, and heaters.
Drastically fluctuating temperatures can also cause buds to drop. So just because you start to see buds forming, don’t assume your cactus is impervious to change. Try to keep the lower temperatures as consistent as possible. Temperatures of 80°F (27°C) or above will prevent your plants from producing flower buds. As much as you may want your plants to be warm and cozy, they actually need those cool days and cooler nights to stay healthy and robust.
Too Much Water
While you might think that a plant whose native habitat is a rainforest should love water, Christmas cactus doesn’t like to have wet feet. A plant that has been consistently overwatered is prone to root rot. This is a deadly situation where roots rot and die, quickly followed by the rest of the plant. If your plant is suffering from overwatering and root rot, it won’t be in the mood to bloom.
Too much water can impact your Christmas cactus in other ways, including a lack of flower buds. Regular watering keeps your plant happy during its active growing cycle. At the end of the growing season, however, the plant wants to go dormant and it directs a final burst of energy into flowering before taking a break from growing.
Coordinate cooler temperatures and longer nights with a reduced watering schedule. During this phase, water your plant only after the soil has thoroughly dried, and water lightly. Rather than soaking the soil, water it only enough to moisten the surface of the soil but not enough to run out the drainage holes. This reduced watering will tell your plant it’s time to produce flowers before dormancy.
Too Much Space
What? Is it even possible to give your plant too much space? If you want your Christmas cactus to bloom, the answer is yes. Believe it or not, these cacti like to be snug in their pots with their roots crowded in.
The best time to repot your Christmas cactus is after it’s finished blooming, not during the active growing season, and definitely not while it’s forming buds or in the middle of blooming. The sensation of being slightly pot-bound is a signal for these plants to produce flowers. In their natural environment, these plants grow in tight spaces so they’re quite content to have their roots be snug in a small space.
When you do decide to repot your specimen, wait until the plant is thoroughly pot-bound. Choose a pot that’s just slightly larger than the current pot so it will fill in the available space quickly and bloom sooner. If your plant is swimming in a pot that’s significantly too large, it will take a while for it to bloom again.
Too Many Moves
Moving a lot is stressful, even for houseplants. During the fall, when your Christmas cactus is preparing to flower, it’s best to keep it in a consistent environment. Don’t move it frequently from one room to another (unless you’re putting it in a dark place for the night). Your plants prefer to feel at home with more subtle changes rather than regular drastic changes.
If you move your plant from a darker room to a lighter room, or from a sunny window to an interior coffee table, you’re forcing it to readjust to a new environment. Too many moves can cause your plant to drop its buds or not form any buds at all. Be especially mindful of moving your plants to a new location during the fall when they are starting to form buds.
Too Much (or Too Little) Fertilizer
Plants need nutrients to grow. Christmas cactus only need to be fertilized during their active growing season, from late winter or early spring until late summer. During late summer and early fall, these plants start to transition to slower growth and, hopefully, flower production.
Stop fertilizing in late summer. This reduction in nutrients will signal these plants to slow down leaf production and focus on flower production. Continuous fertilizing will most likely cause your plants to produce more leaves at the expense of forming flowers. No nutrients at all during the growing season will most likely weaken your plants so they won’t have the energy to bloom, or they’ll bloom only sparingly.
It’s Too Young
Did you propagate your Christmas cactus from cuttings this year? If so, they’ll need some time to grow and mature before they’re ready to form buds. With any luck, they’ll bloom in their second year and if not then, they may need to become a bit more pot-bound before being ready to flower. Be patient and keep caring for your plant; it will bloom when it’s a bit more mature.
Frequently Asked Questions
It’s already Christmas and my Christmas cactus hasn’t bloomed. Can I still force it to bloom this season?
Chances are that if your cactus passes its ideal blooming time without forming any buds, you’ll need to wait until next year. While you’re waiting, take great care of your plant so it has a robust growing season. Now that you know these tips and tricks, you’ll be ready to give your plant the ideal flowering conditions next fall.
Do Christmas cactus and Thanksgiving cactus need the same basic care?
Although Christmas and Thanksgiving cacti look remarkably similar, these are actually two separate species of plants. They bloom close to their namesake seasons but have the same care requirements. Therefore, if you follow the above tips, you can help your holiday cactus bloom right on time, regardless of which species it is. There’s another similar species that blooms in the spring, and it’s known as the Easter cactus.
My Christmas cactus has just a few buds. How can I encourage it to make more flowers?
The tips mentioned here can help your holiday cactus develop buds and produce more abundant buds and flowers. Sparse flowering is most likely related to light exposure and warm temperatures. Next year, starting in early fall, be extra careful to keep your plant in a cool location and give it plenty of uninterrupted dark hours.
Why did the buds fall off my Christmas cactus?
Sometimes, you’ll see your cactus forming buds, and then they all fall off. This is frustrating and disappointing and it is usually preventable. If your plant formed buds and then dropped them, it’s most likely because of one of the following reasons:
- Plant was moved to a different location with different temperature and light conditions.
- Plant was overwatered.
- Temperature was too warm.
- Not enough dark hours each night.
- Significant interruption to the typical environment.
