Plant care
Comfrey-Leaved Rock Rosetemperature & humidity
Cistus symphytifolius
More about comfrey-leaved rock rose
Ideal temperature for comfrey-leaved rock rose
Aim for 2 to 35°C (36 to 95°F) on the thermostat and you've handled the easy part. The hard part is the half-metre around the plant: window glass that drops to near-freezing on a January night, a radiator pumping out hot dry air, a draught from an opened front door. Move the plant 30 cm and you've usually fixed the problem. Below roughly 2°C the damage starts — soft blackened patches, translucent leaves, sometimes overnight.
Cold tolerance & winter care
Comfrey-Leaved Rock Rose is frost-tender (USDA 9-11, RHS H2). 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 comfrey-leaved rock rose
Comfrey-Leaved Rock Rose sits happiest at around Low to moderate, 30–55% relative humidity. Dry air suits this plant best. In humid UK conditions, ensure full exposure to sun and air movement to prevent fungal issues. Avoid planting in sheltered, damp corners; despite needing frost shelter, it should not be overcrowded. 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.
Comfrey-Leaved Rock Rose temperature & humidity — frequently asked questions
What temperature is best for comfrey-leaved rock rose?
Comfrey-Leaved Rock Rose grows best between 2 to 35°C (36 to 95°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 comfrey-leaved rock rose tolerate?
Comfrey-Leaved Rock Rose starts to suffer below roughly 2°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 comfrey-leaved rock rose need?
Comfrey-Leaved Rock Rose prefers about Low to moderate, 30–55% relative humidity. Dry air suits this plant best. In humid UK conditions, ensure full exposure to sun and air movement to prevent fungal issues. Avoid planting in sheltered, damp corners; despite needing frost shelter, it should not be overcrowded.
How do I raise humidity for comfrey-leaved rock rose?
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 comfrey-leaved rock rose live outside?
Comfrey-Leaved Rock Rose is rated for USDA zone 9-11 and RHS hardiness H2. Outside that range it must come indoors before the first frost — treat any outdoor stint as a summer holiday, not a permanent home.
More comfrey-leaved rock rose care
In the UK? Keeping comfrey-leaved rock rose warm in a UK home covers the radiator, single-glazing and heating-season humidity angle. Temperature and humidity are one piece. See the full comfrey-leaved rock rose care guide, its cold-hardiness guide, and watering schedule — humidity and watering problems are easy to confuse.