Plant care
Red-Silk Begoniatemperature & humidity
Begonia rufosericea
More about red-silk begonia
Ideal temperature for red-silk begonia
Temperature kills fewer red-silk 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 16–26 °C (61–79 °F) is fine; the spot you put the plant in matters more. Below roughly 16°C the damage starts — soft blackened patches, translucent leaves, sometimes overnight.
Cold tolerance & winter care
Red-Silk Begonia is frost-tender (USDA 10-12 (indoor in most climates), 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 red-silk begonia
Red-Silk Begonia sits happiest at around 50–70% relative humidity. Maintain moderate to high ambient humidity using a room humidifier or pebble tray, but never mist directly onto the leaves as this triggers fungal disease on the velvety surface. 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.
Red-Silk Begonia temperature & humidity — frequently asked questions
What temperature is best for red-silk begonia?
Red-Silk Begonia grows best between 16–26 °C (61–79 °F). 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 red-silk begonia tolerate?
Red-Silk Begonia starts to suffer below roughly 16°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 red-silk begonia need?
Red-Silk Begonia prefers about 50–70% relative humidity. Maintain moderate to high ambient humidity using a room humidifier or pebble tray, but never mist directly onto the leaves as this triggers fungal disease on the velvety surface.
How do I raise humidity for red-silk 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 red-silk begonia live outside?
Red-Silk Begonia is rated for USDA zone 10-12 (indoor in most climates) 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 red-silk begonia care
In the UK? Keeping red-silk 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 red-silk begonia care guide, its cold-hardiness guide, and watering schedule — humidity and watering problems are easy to confuse.