Are you struggling with your Christmas Cactus not blooming? You aren’t the first because these aren’t your traditional cacti plants that favor desert like conditions.
The Christmas Cactus, along with their relatives of holiday cactus plants (Easter and Thanksgiving Cactus) are part of the Schlumbergera family, all native to the jungles of southern Brazil. The native growing conditions are dry, and dark with moderately low temperatures.
The only way to get a Christmas Cactus to bloom is to plan ahead and coax it into flowering long before you want it to bloom. Generally, preparations start in late September because it takes six to eight weeks of priming the growing environment for buds to sprout at the leaf tips, then eight to twelve weeks from that point for the buds to finally bloom.
Christmas Cactus plants are gorgeous when they’re in bloom and you will see them in their full glorious colors at nursery centers throughout the festive season. The selling point isn’t just their colors that capture the season, but the fact that they’re claimed to be so easy to care for and to get to re-bloom year after year.
The thing is, while they are easy to care for, they do require specific care. That’s the part that’s often left out of the description and that’s what’s cleared up here.
The Specific Steps to Take with a Christmas Cactus Not Blooming
1 – The Daily Dormancy a Christmas Cactus Needs and Why
For a Christmas Cactus to produce flowering buds, it needs plenty of rest beforehand. The part you need to do is mimic the plant’s native growing conditions: Jungle-like conditions, low to the ground, where it’s cool, dark and sheltered from wet.
When you’re growing these indoors, the main problem is lighting. Artificial light can prevent a Christmas Cactus from going into dormancy. The optimal lighting condition you’re aiming to replicate is 8-12 hours of indirect sunlight daily. For 12-16 hours the plant does best when it’s in complete darkness.
This is where things get tricky because depending on where you do your research you could find yourself transferring your plant to a corner in the garage or an insulated shed in your backyard to limit the amount of light reaching the plant. What can happen when you move rooms is the growing environment changes so drastically that it leads to plant shock, doing more harm to the plant than good.
To avoid stressing the plant by altering temperatures suddenly, an ideal solution is to leave the plant in the same growing spot but place a box over it nightly. Just be sure there’s some holes punched into it that are low to the ground to allow for air circulation while still blocking the light from reaching the leaves.
2 – The Temperatures Your Plant Needs Daily and Nightly
Despite the name Christmas Cactus, when not blooming the foliage is still a lush green color and it’s a trailing variety making it ideal to use in a hanging basket outdoors in the summer months.
For optimal protection from winter frosts, hanging plants of Christmas Cacti that you have outdoors should be brought in before temperatures drop below 50°F / 10°C.
Indoors, the temperatures they need are moderately cool. They will need a consistent temperature during the day of around 70°F / 21°C. Most homes are maintained with a room temperature of 72°F / 22°C so you might consider dropping the thermostat slightly or ensuring the plant is in the most shaded part of the room that’s well away from any direct light, in particular, from indoor lighting that may be reflecting heat onto the plant and certainly away from fireplaces and radiators.
During the night, the ideal temperatures are 60-65°F / 15-18°C. If you have independent heat settings for rooms, it would be optimal to lower the room temperature in the room the plant is in as the recommended room temperature for comfortable sleeping is 65-70°F. Keep in mind that if you are placing a container over the plant to block light, the confined space will raise the temperature considerably.
That being said, the lack of light is more important so if you have to choose, limit the light. If you still struggle to get your Christmas Cactus producing buds, it may need to be moved each night to a darker and cooler room in the home. Just as important as darkness is quality indirect daylight for 8-to-12 hours daily.
3 – How Much Water a Christmas Cactus Really Needs
Surprisingly, a Christmas Cactus needs less water to coax it into flowering. When you start forcing the plant into dormancy at the end of September, that’s the time to alter your watering frequency.
At other times of the year, these can be watered weekly or at least when the topsoil is dry to the touch up to a half-inch deep. Don’t allow the soil to completely dry out as that will cause any buds the plant produces to drop from the leaf ends.
When you’re prepping a Christmas Cacti to bloom, let the topsoil dry to a depth of up to 1.5-inches before watering again. You should find one watering lasting the plant two weeks before it needs topping up.
Of course, that depends on the plant pot. If you’ve potted your plant in a terracotta clay pot, those are porous and will need watering more frequently than a plant potted in a plastic container.
4 – Repot Only When the Plant Shows That It Has Outgrown Its Pot Size
The pot size of a Christmas Cactus plays a part in maintaining the plant’s health. It blooms best when the roots are compacted. Many an indoor gardener get anxious when their plants become root bound.
In the case of the Christmas Cactus, it prefers to be root bound because it is a succulent, getting most of its moisture into the leaves from the air rather than the soil. Soil nutrition is only to maintain healthy roots.
Humidity is what keeps the foliage and the roots healthy.
To maintain a stable humidity level, it can be beneficial to place the pot on a shallow tray of pebbles with water. Just make sure the water is shallow enough to prevent the plant pot from sitting in standing water.
Repotting a Christmas Cactus should only need done every few years. Not annually. You’ll know it’s time when you see the roots blocking the drainage holes in the pot. When that happens, if the plant isn’t re-potted, the soil will retain too much of the water so it will need a larger pot but only slightly. Only increase the size of the pot marginally so that the roots remain compacted, but not enough that they’re forced to escape through the drainage holes.
5 – The Balancing Act of Fertilizing Christmas Cactus Plants
Like most plants, the Christmas Cactus does best with a little help in the nutritional department in the form of cactus fertilizers. However, you don’t need to do this every month.
Fertilizer for Christmas Cactus plants only need applied at a rate of once monthly and only from Spring through Summer so just a few months out of the year.
A balanced fertilizer of 20-20-20 is ideal for the Christmas Cactus, but as these aren’t being re-potted annually, the soil can accumulate quite a bit of salt so it is recommended to flush the soil annually. This is done to leach the soil of salts that can become toxic to the plant, which will prevent it from blooming.
A Christmas Cactus that is well-maintained can last for decades with the same potting mix used for three-year cycles, but if you are doing that, you do need to flush the soil each year before you start fertilizing the plant again in the Spring the following year.
3 Common Problems That Prevent a Christmas Cactus From Flowering
1 – Bud Drop
Bud drop is as it sounds – the plant produces the buds, but rather than them flowering, the buds drop off the end of the leaf. It is normal for the plant to drop some buds, but when it drops more than it keeps, that’s a problem you need to address.
The cause is usually related to a watering problem. Too much or too little. Either that or humidity. Change your watering frequency to only when the plant needs it and if you aren’t using a humidity tray to nourish the roots, try doing that so that the plant’s energy focuses on blooming instead of maintaining the roots of the plant.
2 – Root and Stem Rot
Root and stem rot are a fungi infection that affects the plant’s root system. The cause is too much water and it can happen if the soil stops draining as it should, or if you use the wrong potting mix.
To make sure this doesn’t become a problem, when watering the plant, look at the very base of stem. If that’s browning, it is a sign that the soil isn’t properly draining. It will need the soil amended to improve drainage, or re-potted to a more suitable container that allows the water to drain faster.
3 – Discolored Leafs
The most common color variations of the types you don’t want are yellowing and red leaves. The foliage on a Christmas Cactus should always be green. When it fades to a more yellow shade, or worse, starts to turn red, that’s a symptom of sunburn, something that only happens when the plant gets direct sunlight. Lighting should always be indirect. If the leaves on your Christmas Cactus start to yellow or redden, move it to a more shaded area.
The most important thing a Christmas Cactus not blooming needs is darkness for more than 12-hours each night. Light should begin to be restricted at the end of September. Maintain moderately cool temperatures during the day and night, ensuring the plant never gets direct sunlight and adequate watering with fertilizer restricted to only from Spring through to Summer, and you should see your plant producing buds at the leaf tips within 8-weeks of restricting light.
Once you see the plant producing buds, take care with watering to make sure it doesn’t drop the ones it produces.
The buds will gradually enlarge then bloom within 8-to-12-weeks of the buds producing. Start prepping your Christmas Cactus in late September and you should find it’s in full-bloom just in time for the festive season.