Plant care
Sun-Changing Begoniatemperature & humidity
Begonia solimutata
More about sun-changing begonia
Ideal temperature for sun-changing begonia
Temperature kills fewer sun-changing begonia 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 18-26C (64-79F) is fine; the spot you put the plant in matters more. Below roughly 18°C the damage starts — soft blackened patches, translucent leaves, sometimes overnight.
Cold tolerance & winter care
Sun-Changing Begonia is frost-tender (USDA USDA 12+ (RHS H1B); tender — grow indoors or under heated glass below ~10C / 50F, RHS undefined). 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 sun-changing begonia
Sun-Changing Begonia sits happiest at around 60-70% relative humidity. Native to wet tropical Brazil, it thrives in high humidity and is well suited to a terrarium, a bathroom, or a spot near a humidifier. Below about 50% the leaf edges can crisp. Boost moisture with a humidifier or pebble tray rather than misting, which can encourage powdery mildew on the textured foliage. 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.
Sun-Changing Begonia temperature & humidity — frequently asked questions
What temperature is best for sun-changing begonia?
Sun-Changing Begonia grows best between 18-26C (64-79F). 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 sun-changing begonia tolerate?
Sun-Changing Begonia starts to suffer below roughly 18°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 sun-changing begonia need?
Sun-Changing Begonia prefers about 60-70% relative humidity. Native to wet tropical Brazil, it thrives in high humidity and is well suited to a terrarium, a bathroom, or a spot near a humidifier. Below about 50% the leaf edges can crisp. Boost moisture with a humidifier or pebble tray rather than misting, which can encourage powdery mildew on the textured foliage.
How do I raise humidity for sun-changing begonia?
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 sun-changing begonia live outside?
Sun-Changing Begonia is rated for USDA zone USDA 12+ (RHS H1B); tender — grow indoors or under heated glass below ~10C / 50F. Outside that range it must come indoors before the first frost — treat any outdoor stint as a summer holiday, not a permanent home.
More sun-changing begonia care
In the UK? Keeping sun-changing begonia warm in a UK home covers the radiator, single-glazing and heating-season humidity angle. Temperature and humidity are one piece. See the full sun-changing begonia care guide, its cold-hardiness guide, and watering schedule — humidity and watering problems are easy to confuse.