Christmas cactuses seem to have taken a wild turn. Everyone’s into them these days! They’re easy to care for and bring a lot of different colors to your holiday decor.
But there’s one question I’ve heard many times: How much light does this cactus require? Or rather, should you keep it in the dark?
And the answer is…
Do Christmas Cactuses Like Darkness?
… yes and no! These plants do their best blooming in indirect sunlight. They’re not real cactuses, which means they don’t like full sun and direct light.
Yet, that doesn’t mean you should keep them in the dark all year long. Keep your festive cactus in bright indirect sunlight throughout the day and it will flower in time for holidays.
The good news is that these plants can tolerate lower light levels, although constant darkness will reduce blooming.
The Dark Secret To A Blooming Cactus
To get a Christmas cactus to bloom, you’ll need to understand its unique light requirements.
While it thrives in bright, indirect light during most of the year, it requires a specific period of darkness to bloom properly. Unlike many plants, the Christmas cactus needs long nights to set its buds and encourage vibrant flowers.
This is where darkness plays a vital role. Around 12-14 hours of uninterrupted darkness for about 3 weeks is ideal for triggering blooming. So, while it doesn’t like the dark all year round, it does need it to bloom!
Keeping your plant in a location that has low light for an extended period (like a room with no artificial light at night) helps simulate its natural blooming cycle, which is usually triggered by the longer nights in late fall and winter.
But What About Daylight?
Don’t go shoving your Christmas cactus in the closet just yet! Although it loves the darkness to bloom, it still needs light during the day.
The plant thrives best with bright, indirect light. So, if you’re thinking about keeping it in a dark corner of the house to force blooms, that’s not going to work in the long run. M
ake sure to keep your plant in a well-lit spot during the daytime, and then let it rest in the dark at night. A windowsill with sheer curtains is a perfect spot!
Avoid Direct Sunlight
You might be wondering, “What about full sunlight?“.
Full sun can actually harm your Christmas cactus. These plants are native to the tropical rainforests of Brazil, where they grow under the canopy of trees, receiving only filtered sunlight.
If you expose your cactus to direct sunlight, it could scorch its delicate leaves. You’ll notice sunburned spots, or worse, the leaves could start to limp and shrivel.
Temperature Matters, Too
Aside from the light, the temperature plays a significant role in how well your Christmas cactus blooms.
While it’s not as fussy as some plants, it’s important to keep it in a place that doesn’t fluctuate between extremes.
Christmas cactuses prefer cooler temperatures, especially at night, to trigger blooming. Aim for a temperature range of 60-70°F (15-21°C) during the day and slightly cooler at night.
Sudden temperature changes can shock the plant and cause it to drop buds, so try to keep it in a room with consistent temperature.
Avoid placing it near drafts, heating vents, or air conditioners, which can all lead to temperature fluctuations.
How Much Darkness Is Too Much?
Now that we’ve discussed how important darkness is, you might be wondering, how much darkness is too much?
If you leave your cactus in the dark for too long or in a room with insufficient light during the day, it could weaken the plant. Remember, while the darkness is important to trigger blooming, the plant still needs light to stay healthy.
If your plant is struggling to bloom even after receiving 12-14 hours of darkness, it could be a sign that it’s not getting enough light during the day.
Also, don’t leave it in total darkness all year. Give it some break time from the dark period after the blooming season is over.
Once the flowers fall off, let it enjoy normal light conditions again until it’s time to prepare for blooming the next year.
The Right Location For Your Christmas Cactus
The ideal location for your Christmas cactus is one where it can get plenty of indirect sunlight throughout the day and complete darkness during its rest period.
A windowsill facing east or west is perfect – these spots receive bright but indirect sunlight for most of the day, and you can easily place the cactus on a table or shelf to give it the darkness it needs at night.
If you have artificial lights in the room, try to turn them off at night, especially if the room is close to where the cactus is placed. Even a small amount of light during the dark period can disrupt the blooming cycle.
A simple blackout curtain or keeping the plant in a completely dark room can help achieve the necessary darkness during its blooming phase.
Light And Humidity Should Not Be Overlooked
It’s also important to note that Christmas cactuses love humidity. Since they are native to the Brazilian rainforest, they thrive in environments with high humidity.
During the winter months, when homes tend to be drier due to heating, it’s essential to maintain humidity levels.
Consider placing your cactus on a tray with pebbles and water, or use a humidifier to keep the air moist. This will help your Christmas cactus feel more at home and reduce stress, leading to better health and a more vibrant bloom.
Common Mistakes People Make With Light And Christmas Cacti
When it comes to growing a healthy Christmas cactus, it’s easy to make some common mistakes. Here are a few light-related missteps to avoid:
• Too much light – some people place their Christmas cactus in direct sunlight, thinking it will thrive. As mentioned earlier, too much direct sunlight can burn the leaves. Make sure you provide bright but indirect light for optimal health.
• Not enough darkness – If you want your Christmas cactus to bloom, it needs those long, dark nights to stimulate its growth cycle. Don’t forget to give your plant a chance to rest in the dark during the blooming season.
• Light disruptions – If you leave lights on in the room, even if it’s for just a few hours at night, it could interfere with the plant’s blooming cycle. Make sure to keep the lights off at night during the crucial blooming period.
When Do Christmas Cactuses Flower?
As the name suggests, Christmas cactuses produce blossoms around Christmas. Of course, their entire flowering season is a lot longer than a couple of days.
Christmas cactuses start flowering in November and finish their blooming cycle around January.
It may take up to 12 weeks for the buds to develop into real flowers, so make sure to time the dormancy and darkness period accordingly.
What Happens If Your Christmas Cactus Doesn’t Bloom?
If your Christmas cactus isn’t blooming despite giving it the proper dark period, there could be other factors at play.
Ensure that your plant is getting enough indirect sunlight during the day and the right temperature.
Also, be sure to avoid overwatering. An overly wet plant can suffer from root rot, which stunts growth and prevents blooming.
Fertilizing with a balanced fertilizer once a month during the growing season can also promote healthy growth.
Sometimes, older plants may need to be repotted. A cramped pot can limit root growth and stunt flowering.
If you notice that your cactus hasn’t been blooming as much as it did in previous years, repotting may give it the boost it needs.