Every other plant in the house is shutting down in November. Growth stops, leaves drop, everything waits for February. The Christmas cactus does the opposite: it waits until the light goes, and then it flowers.
That is a botanical fact and it is also, if you want it to be, a thing worth handing somebody in their worst month.
it blooms in the darkest months
The Christmas Cactus
Buy it now and the person receiving it watches it flower through November and December.
From $30, free shipping over $90
Send one nowWhy it flowers when everything else stops
Schlumbergera is a short-day plant, which is a slightly misleading name: what it is actually measuring is the length of the night.
Once nights run to twelve or fourteen hours of genuine darkness, and the temperature sits somewhere between 55 and 65 degrees, the plant reads that as its season and starts setting buds. Six weeks or so later, it flowers. In the northern hemisphere that lands in late November and December, which is how it got the name.
It is not a desert cactus either, which is the other thing people get wrong. It grows in the coastal mountains of southeastern Brazil, in the crooks of trees, in leaf litter, in shade and humidity. That is why it wants more water than a cactus and resents direct sun.
How to make one bloom
This is the most searched thing about this plant, and the answer is short.
- Darkness, uninterrupted. Twelve to fourteen hours a night for about six weeks. A spare room, a cupboard at night, anywhere a lamp will not come on. A single lit evening in the middle of it can reset the clock.
- Cool. 55 to 65 degrees at night. A windowsill away from the radiator does it.
- Less water while it is setting buds. Let the top inch dry out. Then water normally once the flowers open.
- Then stop moving it. Once the buds appear, leave the pot exactly where it is. Turning or relocating a budding Christmas cactus is the classic way to make it drop every single bud, and it will.
If yours did not flower last year, the cause is almost always a light at night or a warm room, not anything you did to the soil.
What it means, and why it is not in a holiday collection
We file it under In Your Grief, and that is deliberate.
The holiday framing is an accident of the calendar: it is called a Christmas cactus because of when the nights get long in the hemisphere that named it. Sold as festive decor it is a seasonal object that goes in a cupboard in January.
Read the other way, it is one of the few honest things you can send somebody having a terrible winter. It does not insist that they cheer up. It just demonstrates, on the windowsill, that the dark part is when some things open. For a first Christmas after a loss, when the calendar itself turns cruel, that is a steadier gift than anything with a bow on it.
Buy it in October, not December
The whole point of this plant is the watching.
Sent now, it arrives before the buds form, settles into its spot, and then does the thing over the following weeks while the person has it. Sent on December 20th in full flower, it is a bouquet with a pot: beautiful for a fortnight, and they missed the part that made it worth sending.
There is a practical reason too. Moving a plant in bud makes it drop the buds, so a cactus shipped in December often arrives having thrown off exactly what you paid for.
For the same winter
Christmas, Thanksgiving or Easter cactus
Three near-identical plants that bloom at different points, and most shops label them interchangeably.
| Segment edges | Flowers | |
|---|---|---|
| Thanksgiving · S. truncata | Pointed, claw-like teeth | November |
| Christmas · S. buckleyi | Rounded, scalloped | December into January |
| Easter · Rhipsalidopsis | Smooth, with small bristles | Spring |
Most plants sold as Christmas cactus in the US are in fact Thanksgiving cactus, which is good news rather than a swindle: it flowers a few weeks earlier, so a plant bought in October tends to be in bloom by late November.
It is safe around pets
Unlike most of what sits on a windowsill in December, Schlumbergera is non-toxic to cats and dogs. Poinsettia, holly, mistletoe and amaryllis are all worse choices in a house with an animal in it, and the first three get sent as gifts constantly.
for somebody having a hard winter
The Christmas Cactus
Sent in October, it flowers in their house rather than arriving already done.
From $30, free shipping over $90
Send one nowWe write one of these a week.
One plant, what it means, and who to send it to. No offers, no noise.