Plant care
Mandarin orangetemperature & humidity
Citrus reticulata
More about mandarin orange
Ideal temperature for mandarin orange
Temperature kills fewer mandarin orange plants than you'd think. What kills them is the micro-climate within a normal-temperature room — a leaf pressed against single-glazed winter glass, the hot dry updraft directly above a radiator, the cold blast from an AC vent. The thermostat reading at 15–30°C optimal; satsumas tolerate -4 to -7°C briefly (59–86°F optimal; satsumas to 20–25°F briefly) is fine; the spot you put the plant in matters more. Below roughly 15°C the damage starts — soft blackened patches, translucent leaves, sometimes overnight.
Cold tolerance & winter care
Mandarin orange is frost-tender (USDA 8-11, RHS H1b). It cannot survive a frost, so in most of the US and UK it lives indoors year-round or summers outside and comes back in well before the first autumn frost — once nights drop toward 10-12°C is the cue, not the first frost warning. Acclimate it over a week when moving between indoors and out so the leaves do not shock.
Humidity for mandarin orange
Mandarin orange sits happiest at around Moderate, 50–60% relative humidity. Tolerates a wider humidity range than some citrus. Indoor trees appreciate misting or a humidity tray in dry centrally heated environments. Adequate airflow around foliage reduces fungal disease risk in high-humidity situations. The usual low-humidity tell is crisp brown leaf tips and edges while the soil moisture is fine — a sign the air, not the watering, is the problem. If you need to raise it, the reliable methods are grouping plants together, standing the pot on a tray of damp pebbles (the pot above the waterline, never in it), or running a small humidifier in winter when indoor heating dries the air most. Misting is the least effective — it raises humidity for minutes, not hours.
Mandarin orange temperature & humidity — frequently asked questions
What temperature is best for mandarin orange?
Mandarin orange grows best between 15–30°C optimal; satsumas tolerate -4 to -7°C briefly (59–86°F optimal; satsumas to 20–25°F briefly). Keep it out of cold draughts, off freezing windowsills in winter, and away from the hot dry air directly above radiators — the extremes matter far more than the average room temperature.
How cold can mandarin orange tolerate?
Mandarin orange starts to suffer below roughly 15°C. It is frost-tender and will be damaged or killed by a frost, so bring it indoors once nights fall toward 10-12°C.
What humidity does mandarin orange need?
Mandarin orange prefers about Moderate, 50–60% relative humidity. Tolerates a wider humidity range than some citrus. Indoor trees appreciate misting or a humidity tray in dry centrally heated environments. Adequate airflow around foliage reduces fungal disease risk in high-humidity situations.
How do I raise humidity for mandarin orange?
Group it with other plants, stand the pot on a tray of damp pebbles (kept above the waterline), or run a small humidifier in winter. Misting only helps for a few minutes, so it is the weakest option for a plant that genuinely needs more humidity.
Can mandarin orange live outside?
Mandarin orange is rated for USDA zone 8-11 and RHS hardiness H1b. Outside that range it must come indoors before the first frost — treat any outdoor stint as a summer holiday, not a permanent home.
More mandarin orange care
In the UK? Keeping mandarin orange warm in a UK home covers the radiator, single-glazing and heating-season humidity angle. Temperature and humidity are one piece. See the full mandarin orange care guide, its cold-hardiness guide, and watering schedule — humidity and watering problems are easy to confuse.