If you want to make sure your Christmas cactus blooms this year, you’ve got to understand one thing: light matters, and so does darkness. The whole blooming process is triggered by a balance between light exposure and total darkness. So, the “dark shade” trick isn’t just some old gardener’s tale—it’s actually part of the plant’s natural rhythm.
So when to put your plant in dark shade? You’ll want to start giving your Christmas cactus extended periods of darkness around 6 to 8 weeks before you want it to bloom. If you’re aiming for those classic Christmas blooms, that means early to mid-October is your golden window. The plant needs 12 to 14 hours of complete darkness each night—yes, complete. Even a nightlight or a lamp across the room can disrupt the cycle.
During the day, place your cactus in bright but indirect light. At nighttime, let’s say around 6PM, move it back to a dark closet or cover it with a box or blackout cloth. It may sound like a hassle, but it’s worth it when those buds start forming. You’re simulating the natural light cycles of its native Brazilian habitat, where day length shifts trigger blooming.
I’ve found it helpful to set my clock every day at certain times (normally 6PM and 8AM), to remind me when to put the cacti in shade, and in the morning back to light.
So, in a nutshell: When it’s time to start prepping for the blooming season, put your Christmas cactus in the dark at night only, and keep it in filtered light during the day. If you nail the light/dark routine and pair it with the right temps (we’ll get into that next), you’ll be rewarded with blooms that last for weeks.
Christmas Cactus Temperature Range
Temperature is another big lever you can pull to help your Christmas cactus thrive—and bloom on schedule. Unlike a lot of fussy tropical plants, your Christmas cactus (as well as Thanksgiving cactus) actually likes cooler temperatures, especially at night.
Here’s the ideal spots: During the day, keep it around 60°F to 70°F (15°C to 21°C). At night, let it dip down to 50°F to 55°F (10°C to 13°C). That gentle temperature drop at night mimics the natural environment this plant evolved in, which tells the cactus it’s almost time to bloom.
Now, you don’t have to be obsessive with a thermometer, but if you’re trying to get blooms going, it’s worth paying attention. If your house stays too warm—like 75°F (24°C) or above all the time—it might delay or prevent blooming altogether. On the other hand, if it gets colder than 50°F (10°C) regularly, you can stress the plant.
One easy trick: if you’ve got a cool spare room or a sunroom that isn’t heated at night, that’s a great place for your cactus during its bloom prep period (usually October-November). Just remember—cool, not cold, and definitely no drafts.
In summary: keep things mildly cool during the day and a bit chilly at night, especially in the lead-up to blooming. Combine that with the right dark schedule, and you’re on the path to a very festive plant.
Is Christmas Cactus Cold Tolerant?
When I was younger, I had this beautiful Christmas cactus I got from my great-aunt. Every summer, I’d move it outside, and it always seemed to thrive in the fresh air. But one autumn, I let the time slip and wasn’t paying attention to the weather, and one night the temperature had dropped below freezing! By morning, the leaves were limp and mushy—it had frozen. I immediately brought it indoors and hoped it would bounce back, but it didn’t. That was a shame… Christmas cacti might love the outdoors in summer, but they absolutely can’t handle frost. But yeah, lesson learned—always keep an eye on the forecast! (And especially if you live in a cooler climate)
Despite the name “cactus,” the Christmas cactus is not a desert dweller—it’s a tropical epiphyte. That means it grows on trees in the cloud forests of Brazil, soaking up humidity and filtered light. So no, it’s not cold hardy, at least not in the way a desert cactus is.
Your Christmas cactus can survive short dips into the high 40s°F (around 8°C) without harm, but once you get below that, you’re asking for trouble. Freezing temps? A definite no-go. Even just one night of frost can cause irreversible damage—soft, mushy leaves, dropped buds, or worse, a dead plant.
The danger zone starts below 50°F (10°C). If you’re leaving your plant outside in early fall or late spring, keep an eye on the weather. A surprise cold snap can sneak up fast, especially if the plant is in a pot and not insulated by surrounding ground.
Also, watch for cold drafts indoors. A window that feels fine during the day might chill the plant too much at night. You might not notice, but your cactus will.
So, in short: Christmas cacti are mild cold-tolerant, but only for short periods and never near freezing. Treat them like a tropical friend who enjoys sweater weather—but absolutely hates winter coats.
Growing Christmas Cactus Outdoors (Full-Time)
Are you thinking about letting your Christmas cactus live outside all year, and wondering if it’s possible? Yes, it’s possible—but it only works in very specific climates.
If you live in USDA zones 10 to 12, like parts of Florida, southern California, or Hawaii, you might be able to grow them outdoors full-time. These zones stay mild year-round and never dip below freezing. Even then, you still want to give it protection from harsh sun, heavy rain, and sudden temperature swings.
Outside those zones? Don’t do it. Your Christmas cactus won’t survive the winter because even a light frost can kill it. If you’re in zones 9 or lower, like my beloved New Orleans, you can keep it outside, but you should bring it indoors for fall, winter, and part of spring. No exceptions.
Even in warm zones, consider using a container or hanging basket that will make it easier to move the plant around to follow the ideal light and temperature. Outdoors, it should live in dappled shade, like under a tree canopy or on a sheltered patio. Too much sun will scorch it, and too much rain can cause rotting issues.
In other words, full-time outdoor growing is possible—but it’s really only suited for a specific kind of plant parent in just the right kind of climate. For the rest of us, however, only part-time outdoor growing works for our Schlumbergeras.
Putting Christmas Cactus Outdoors for Summer
If the climate doesn’t allow you to keep your cacti outside the whole year (if only all of us could live in a paradise), then part-time (/summer) is a great option. It’s like giving your Christmas cactus a ‘vacation’ outdoors in the summer. It’s also a simple way to help it grow stronger and bloom better, and best of all, it’s as close to ‘nature’ as simply possible. There are just a few aspects to consider if you want to try outdoor growing with your holiday cacti.
Start by waiting until all danger of frost has passed, usually around late spring. Think consistent nighttime temps above 55°F (13°C). Then, ease your plant into the change. Don’t just toss it in full sun and wind—it can’t handle it! Start in a shady, sheltered spot, like under a porch.
I wouldn’t start with a full 24 hours right away. I’d start slowly and let them get used to the outside conditions before leaving them there full-time. As with young tomato plants, you slowly introduce them to the outside world. Once they’re used to it, you can leave them there full-time.
After a week or two, when the plant seems to have adapted to its new surroundings, you can move it to brighter filtered light if it seems happy—but still, no hot direct sun!
Outdoors, your cactus will benefit from better air circulation, natural humidity, and light rain. When it comes to watering, don’t rely on rainwater alone—even outside; make sure the soil drains well, and only water when the top inch feels dry. If your plant is exposed (no roof), too much rain can quickly cause rot issues.
Here’s the best part: that gradual exposure to real sunlight and slight temperature shifts over summer actually primes your cactus for fall blooming. Just remember to bring it back inside in early autumn, before nights drop below 50°F (10°C). And even during the summer months, keep an eye on the temperatures—and especially if you live in an unsteady climate, even during the summer months!
So, yes—summer outside? You can totally do this. Just ensure shade, good airflow, no overwatering, and a graceful return indoors when the season turns.
I’d say the only con with keeping them outdoors is pests. It doesn’t always happen, but it can. Pests are the reason I don’t personally put my cacti outdoors anymore in the summer. But that doesn’t mean you shouldn’t! Plenty of people do it, and their plants are just fine. Just be aware of it, that’s all.
FINAL WORDS:
I hope all your questions got answered regarding shade, temperature, and outdoors growing. If you have any questions, please write in the comment section below. Are you planning to keep your holiday cacti outdoors—full-time, part-time?
Thank you so much for reading. Happy growing, everyone!
Until next time… 💚
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