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Christmas cactus

Schlumbergera truncata, Cactaceae

Sources last read 14 September 2026.

Middling It gives warning, with time to act.

Also called Claw Cactus, common winter cactus, crab cactus, Crab's Claw Cactus, False Christmas Cactus, Holiday Cactus, lobster cactus and Thanksgiving Cactus.

Christmas cactus (Schlumbergera truncata), the whole plant.
Leo Michels, Public domain · Wikimedia Commons

Toxicity is partly unassessed

  • Not assessed for cats. This plant is not on the ASPCA list. That is not a finding of safety: none of the sources read for this site gives an answer either way. Treat it as unknown.
  • Not assessed for dogs. This plant is not on the ASPCA list. That is not a finding of safety: none of the sources read for this site gives an answer either way. Treat it as unknown.
  • Not assessed for people. RHS publishes no harm statement for this plant. That is not a finding of safety: none of the sources read for this site gives an answer either way. Treat it as unknown.

What the sources say about its care

Light
Partial shade
RHS · read 13 September 2026
Water
Well-drained or Moist but well-drained
RHS · read 13 September 2026
Humidity

No source read publishes a humidity figure for any plant on this site. What follows is general guidance for foliage plants.

Most foliage plants prefer more humidity than a heated room gives; succulents are named as an exception
Penn State Extension · read 13 September 2026
Temperature

How cold this tolerates, not what it prefers. No source read for this site publishes a preferred range for a plant indoors.

H1B — 10–15°C 10–15 °C
RHS · read 13 September 2026
Soil
Sand, Loam; pH Acid or Neutral
RHS · read 13 September 2026
Toxic to cats
Not on the ASPCA list. That is not a finding of safety.
ASPCA · read 13 September 2026
Toxic to dogs
Not on the ASPCA list. That is not a finding of safety.
ASPCA · read 13 September 2026
Harmful to people
No statement of harm to people is published for this plant; that absence is not evidence it is safe.
RHS · read 13 September 2026

How it usually goes wrong

Growth slows and what does arrive is thin

The newest leaves on the Christmas cactus are the palest and smallest, and the stems carrying them bend toward the brightest side of the room.

Partial shade is where its source places it. Below that the plant spends stored sugar faster than it makes it, and reaching is what that looks like from outside.

Telling it apart: Spacing. A plant short of light stretches; one short of nitrogen keeps its spacing and only loses colour.

RHSChristmas cactus leggy, leaning growth: causes
Leaves turn glassy from the stem outward

The Christmas cactus leans in its pot as the tissue at soil level softens, and the lowest leaves drop whole.

Plants that store water in their tissue take it up readily and release it slowly. In soil that stays wetter than the well-drained or moist but well-drained its source describes, the stored tissue breaks down.

Telling it apart: Firm and wrinkled is thirst; soft and swollen is the opposite. The two look similar from across a room and feel nothing alike.

RHSDiagnose a soft, mushy stem on this Christmas cactus
Lower leaves collapse and yellow within days of a watering

On a Christmas cactus the yellowing climbs from below. Affected leaves feel limp rather than papery, and water sits in the saucer long after it drains through.

The source for this plant describes well-drained or moist but well-drained soil. Compost that stays saturated loses the air spaces fine roots grow into, and those roots die back first.

Telling it apart: Weigh the pot in your hand. A pot still heavy a week after watering is holding more water than the roots are using.

RHSDiagnose yellowing leaves on this Christmas cactus

Not sure which it is? Ask the diagnosis questions for Christmas cactus.

Routine care

Watering
Set the stem segment in moist potting mix that drains well, and water once the mix has dried completely.
NC State Extension · read 13 September 2026
Feeding
Start monthly feeding when new spring growth appears, then feed less in fall and early winter.
NC State Extension · read 13 September 2026
Repotting
Give it a new pot about every three years, since it grows well when a little pot-bound.
NC State Extension · read 13 September 2026
Propagation
Stem cuttings root readily.
NC State Extension · read 13 September 2026
Increase from stem cuttings.
RHS · read 13 September 2026
Pruning
Pruning is not needed.
RHS · read 13 September 2026
Pests and diseases
Can be troubled by scale insects and mealybugs.
NC State Extension · read 13 September 2026
Mealybugs can occur. Diseases: usually none.
RHS · read 13 September 2026

Move something and watch

Loading the simulator. It needs JavaScript; the care table above does not.

About the plant

Schlumbergera truncata, the false Christmas cactus, is a species of plant in the family Cactaceae. It is endemic to a small area of the coastal mountains of south-eastern Brazil where its natural habitats are subtropical or tropical moist forests. It is the parent or one of the parents of the houseplants called Christmas cactus, Thanksgiving cactus or zygocactus, among other names.

From Wikipedia, CC BY-SA 4.0 · read 13 September 2026

Native range
SE. Brazil
World Checklist of Vascular Plants, June 2026 release, CC BY.
Kew WCVP · read 13 September 2026
Southeastern Brazil
NC State Extension · read 13 September 2026
Climate
wet tropical
World Checklist of Vascular Plants, June 2026 release, CC BY.
Kew WCVP · read 13 September 2026
Growth form
succulent epiphyte
World Checklist of Vascular Plants, June 2026 release, CC BY.
Kew WCVP · read 13 September 2026
Epiphyte, Herbaceous Perennial, Succulent; habit arching, multi-stemmed, rounded, weeping
NC State Extension · read 13 September 2026
Trailing (evergreen)
RHS · read 13 September 2026
Size
Height 9–12 in; width 12–24 in
NC State Extension · read 13 September 2026
Height 0.1-0.5 metres; spread 0.1-0.5 metres after 5–10 years
RHS · read 13 September 2026
Flowering
Flowers orange, pink, purple/lavender, red/burgundy, white; blooms in fall, winter
NC State Extension · read 13 September 2026
Flowers purple in autumn and winter; red in autumn and winter; pink in autumn and winter
RHS · read 13 September 2026
Uses

What sources record people using this plant for. A traditional or medicinal use listed here is a record of use, not advice to eat it or treat anything with it.

Has medicinal, environmental and food uses.
NC State Extension · read 13 September 2026

Common problems with Christmas cactus

Other Schlumbergera

More of the Cactaceae family

Plants with similar care

Sources

What this does not cover

The figures above are what published sources say, not measurements of the plant in your room. They say nothing about your pot size, your water, the season, or how far from the glass the plant stands, and those decide more than any figure here does.

Humidity has no species figure because no source read for this site publishes one, and the only temperature published for this plant is a cold floor. The simulator fills those gaps with general figures for its kind of plant, marked as general and listed on how we read sources. Where a toxicity row says the plant was not assessed, that is the absence of a finding and not a finding of safety.

If something is already wrong, the diagnosis tool asks about the soil, the window and the watering, which is where the answer usually is.