Christmas cactus

True Christmas cactus

Segments have rounded, scalloped edges (no sharp teeth). Flowers slightly more pendulous and almost actinomorphic. Blooms genuinely around Christmas (late Dec–Jan); S. truncata typically peaks in Nov–Dec.

Easter cactus

Segments have smoother edges with tiny bristles at the apex. Flowers are radially symmetrical (star-shaped) and bloom in spring (March–May). Often sold alongside Schlumbergera and routinely confused.

Queen of the night

Much larger plant with broad, strap-like stem segments and huge white night-blooming flowers. Different genus and a very different scale.

Bright indirect light — no harsh midday sun.

Schlumbergera grows under broken canopy in Brazilian Atlantic Forest — bright but filtered. Indoors, an east window is ideal year-round; a south or west window works behind a sheer curtain. Direct summer sun bleaches segments to pale yellow or red and can scorch them within hours. In Nordic winters, give the brightest spot you have — short days from October onwards are a feature, not a problem, and trigger budding.

Seasonal: Move outdoors to dappled shade after the last frost in summer if you want extra-vigorous growth; bring it back inside well before nights drop below 5 °C.

When the top 2–3 cm of soil is dry — every 7–10 days in growth.

Despite being a cactus, Schlumbergera is not a desert plant. The native habitat is humid mountain forest, and the plant needs even moisture during active growth. Water thoroughly until water runs from the drainage holes, then empty the saucer. Allow the top 2–3 cm to dry before the next watering. Drying out completely causes segment drop and bud abortion; staying soggy causes root rot. Reduce frequency in winter but never let the plant bone-dry.

Seasonal: Cut watering by half during the 6–8 week 'rest' period in early autumn that triggers budding — let the soil get drier than usual to stress-flower the plant.

Well-draining mix — chunky and slightly acidic.

A 2:1:1 mix of standard indoor potting soil, coarse perlite, and orchid bark mimics the epiphytic mountain habitat. A cactus-and-succulent mix amended with extra organic matter (one part peat or coco coir to two parts succulent mix) also works. Avoid pure desert-cactus mix — too lean and gritty for this species.

40–60 % preferred — tolerates standard Nordic indoor humidity.

Higher humidity helps but is not critical. Schlumbergera handles 30 % without leaf drop, though buds may abort in very dry air during heating season. Group with other plants or run a small humidifier nearby in winter if you find segments shrivelling. Misting is unnecessary and can encourage stem rot at the joints.

16–24 °C in growth; 10–15 °C nights for 6–8 weeks to set buds.

Schlumbergera evolved at 700–1,500 m elevation where nights are cool. Indoors, normal room temperatures (18–22 °C) suit it most of the year, but to bloom reliably it needs a 6–8 week 'cool rest' from mid-September: night temperatures below 16 °C and 12+ hours of uninterrupted darkness. A cool windowsill in an unheated bedroom or porch is perfect. Above 21 °C at night, bud initiation is suppressed.

Seasonal: Tolerates brief drops to 4 °C but loses segments below freezing. Never expose to frost.

Half-strength balanced liquid feed monthly in spring and summer.

Feed monthly from April through August with a balanced liquid fertiliser at half label rate. Switch to a high-potassium 'tomato' feed in September to support flower development. Stop feeding once buds open and resume after flowering in late winter. Over-fertilising produces lush green segments but few flowers.

Seasonal: No feeding during the cool rest period or in mid-winter.

Pinch back segments after flowering to encourage branching.

After the last flowers fade in late winter, twist off 1–2 segments from the tips of leggy stems. The plant branches at each cut within 4–6 weeks, producing a denser, more flower-prone shape. Pruned segments root readily as cuttings.

Every 3–4 years in late winter; loves to be pot-bound.

Schlumbergera flowers most prolifically when slightly pot-bound, so resist the urge to repot annually. Move up by a single pot size only when roots fill the pot and water runs straight through. Repot in late winter just as the plant breaks dormancy. A wider, shallow pot suits the shallow root system better than a deep one.

No documented toxicity to humans. Schlumbergera contains no known toxins; ingestion may cause mild GI upset, like any non-food plant.

Listed by ASPCA as non-toxic to cats. Mild GI upset is possible with any plant ingestion.

Listed by ASPCA as non-toxic to dogs. Mild GI upset is possible.