Houseplant · Cactaceae
Christmas Cactus
Schlumbergera × buckleyi
Offer it bright, indirect light and cool fall nights, and this forgiving old houseplant will bloom right on time for the holidays.
Bright indirect
55–81°F · 13–27°C
USDA 10–12
6–12 in · 15–30 cm
Overview
The Christmas cactus comes from the forest, not the desert, and that small fact takes a lot of the worry out of growing it. In the wild it lives high in the trees of the Brazilian rainforest, roots tucked into pockets of leaf litter, which is simply why it likes steadier moisture than the spiny cacti most people imagine. Kept indoors it stays small and can live for decades, often handed down from one gardener to the next, so the plant on your shelf may well outlast many of your other green companions.
The best part is the way it times its flowers. As the days grow short and the nights turn cool in fall, the plant reads the change and sets buds, then opens into arching, tubular blooms in pink, red, white, or coral right around the holidays. Its flat, jointed segments give it a soft, cascading shape that looks lovely spilling from a hanging basket or over the edge of a shelf, and seeing those buds appear is a real reward.
Once you understand the one simple trick of light and cool nights, this plant asks for very little. Keep it in bright, indirect light, water it when the top of the mix has dried, and try to resist hovering over it. A plant left a touch pot-bound and undisturbed is the very one that flowers best, so a little benign neglect is exactly what it wants from you.
Care
The short version: give it bright, indirect light, water once the top of the mix has dried, and offer a stretch of cool nights with long, unbroken darkness in fall so the buds can set.
Light
Give it bright, indirect light for most of the year and it will thank you. It manages in medium light or light shade too, though harsh direct summer sun can scorch the segments and tint them red. An east window, or a west one with some shade, makes a comfortable home for it.
Water
Water once the top half of the mix has dried, then water it well. Remember this is a forest cactus, so it enjoys more moisture than a desert cactus but should never sit in soggy soil. After buds appear, keep the mix evenly moist, since a dry spell at that moment is what makes the buds drop.
Soil
Settle it into a well-drained, organic-rich potting mix, the sort sold for cacti or succulents with a little extra grit worked in. A pH between 5.5 and 7.0 keeps it content. Good drainage matters most of all, because standing water at the roots is the one thing that truly harms these plants.
Temperature
Everyday room warmth between 55°F and 81°F (13°C to 27°C) keeps it happy through the year. The one exception is fall, when cool nights around 55°F to 60°F (13°C to 16°C) become part of what coaxes it into bloom.
Humidity
Average household humidity is plenty, so there is no number you need to chase. Being a rainforest plant it does enjoy a little extra moisture in the air, and simply grouping it with other plants or setting it on a pebble tray covers that with no bother.
Feeding
Feed it monthly through spring and summer while it is growing, using a balanced houseplant fertilizer at half strength. Ease off by late summer to gently steer it toward fall flowering, and switch to a low-nitrogen, high-phosphorus feed as bloom season draws near.
Pruning
Once it has flowered in spring, pinch or twist off a few end segments to encourage branching and a fuller, bushier shape. Nothing goes to waste, since the pieces you remove root easily into brand new plants for you to keep or give away.
Repotting
Repot only every 3 to 4 years, and there is no need to hurry. This cactus blooms best when kept slightly pot-bound, so an overly roomy pot gives you more leaves but fewer flowers. Roots peeking from the drainage holes, or soil that dries almost the moment you water, will tell you when the time has finally come.
Size & spacing
A grown plant stays compact at 6 to 12 inches (15 to 30 cm) tall, yet it can reach 12 to 24 inches (30 to 61 cm) across as the jointed stems arch and trail. That soft, cascading habit makes it a natural choice for a hanging basket or a high shelf where it can spill freely.
Troubleshooting
Most Christmas cactus hiccups trace back to water, light, or the conditions it needs to flower, and the plant lets you know in plain ways. Dropped buds, soft stems, or color creeping into the segments are all little messages. Find what matches yours below and make a small change early, while it is still an easy fix.
Soft, drooping stems sitting over soil that won't dry
If the plant flops while the soil stays wet, the trouble is root rot, brought on by too much water or a dense mix that holds it. Slip the plant out and feel the roots, and should they be brown and soft instead of firm and white, all is not lost. Let it dry out, trim the rotted roots away, and repot into fresh, fast-draining mix, then tip out the saucer so the pot never sits in standing water.
Fix:
- Allow the plant to dry out
- Repot into a fresh, fast-draining mix and trim away rotted roots
- Empty saucers so the pot never stands in water
Yellowing buds that let go before they open
Try not to worry if you see bud drop, because it nearly always follows one sudden change after the buds have formed, such as a cold draft, a warm vent, or a watering you forgot. Settle the plant in one calm spot and keep the soil evenly moist while it carries buds. It just prefers to stay put, so leave it be and skip even a gentle turn until the flowers open.
Fix:
- Keep the plant in a stable spot away from heat vents and cold drafts
- Keep the growing medium evenly moist once buds appear
- Avoid moving or rotating the plant while in bud
A healthy plant that just won't flower yet
A plant that won't bloom is almost always one that stayed too warm and too bright through fall, and that is an easy fix. Buds appear only after a run of cool nights around 55°F to 65°F (13°C to 18°C) along with 12 or more hours of unbroken darkness each night for roughly 6 weeks. Even one lamp clicking on during that dark stretch can hold the flowers back, so a quiet, dim corner is all it really needs.
Fix:
- Provide cool nights of about 55 to 65°F
- Give 12 or more hours of continuous darkness each night for roughly 6 weeks starting in fall
- Avoid interrupting the dark period with artificial light
Segments taking on a yellow or red tinge
When segments flush yellow or red, they have simply caught a sunburn from too much direct light, which happens most in summer. Shift the plant into bright, indirect light and let it rest in a little shade through the hottest weeks. The color tends to ease back once that harsh sun is off the leaves, so this one rights itself with a small change.
Fix:
- Move the plant to bright, indirect light
- Provide light shade during hot summer months
Toxicity
Here is some welcome news for pet owners: the Christmas cactus is safe. The ASPCA lists it as non-toxic to cats and dogs, and it holds no poison that would threaten other animals or people. A pet that chews a good amount of the fibrous stems may get a brief, mild stomach upset, but that is truly as far as it goes.
Safe for
People · Cats · Dogs · Horses · Rabbits · Livestock · Birds
Cats None
You can relax about a curious cat here, because this plant carries no toxin at all. A cat that chews through a good bit of the fibrous stems might just have a passing spell of vomiting or a loose stool, and it settles on its own.
Dogs None
There is nothing poisonous in this plant for a dog. If yours grabs a big mouthful of the stems, the most you are likely to see is a short, mild upset tummy that clears up without any fuss.
Horses None
Rest easy, since nothing in this plant harms horses, and its small indoor size means a horse would seldom come near it anyway.
Rabbits None
A rabbit can nibble the segments with no harm done. Like any leafy green, a really big helping might loosen the gut for a day, but there is no danger in it.
Livestock None
This plant holds no toxin that bothers goats, sheep, or cattle. Kept as a houseplant, it hardly ever ends up where farm animals can reach it.
Birds None
A pet bird faces no poisoning risk from the stems or flowers, so an odd peck is nothing you need to fret over.
People None
This one is not poisonous to people, little ones included. It is not meant for eating, so there is no reason to taste it, but a curious bite will do no harm.
Varieties
Three holiday cacti tend to show up under the same name, and once you know the cues, telling them apart by segment shape and bloom time is simple. Here are the ones you are most likely to meet.
Thanksgiving cactus (Schlumbergera truncata)
You can spot it by the pointed, claw-like teeth running along its segment edges and by its bloom near Thanksgiving, and most plants sold as Christmas cactus are really this one.
True Christmas cactus (Schlumbergera × buckleyi)
This kind shows rounded, scalloped segment margins and a gentle drooping habit, and it opens its flowers closer to Christmas than its earlier cousin.
Easter cactus (Rhipsalidopsis / Hatiora gaertneri)
This belongs to a different genus, with rounded segments edged in tiny bristles and flowers that wait to open in spring.
How to propagate
Few houseplants are this forgiving to multiply. A twisted-off piece of stem roots almost on its own with hardly any effort from you, which is exactly how these plants get shared from friend to friend.
Stem cuttingsEasy
Late spring to early summer after flowering (about May to June) · Roots form in about 2 to 8 weeks
Take your cuttings in late spring to early summer once flowering wraps up, around May to June, and don't be nervous about it. Gently twist off a piece of 2 to 5 joined segments, leave the cut end to callus for a day, then settle it into a moist, well-draining mix. The segments take root with little fuss in about 2 to 8 weeks, and popping a humidity cover over them gives a helpful nudge.
Myths
All three holiday cacti are one and the same plant, so segment shape and bloom time make no difference.
They truly are different plants, and once you know the cues you can tell them apart with ease by segment shape and flowering time. Thanksgiving cactus carries pointed, claw-like teeth and blooms in late November, true Christmas cactus has rounded, scalloped margins and opens nearer Christmas, and Easter cactus is a separate genus that holds off until spring. Most plants sold as Christmas cactus are actually Thanksgiving cactus.