Plant care
Sempervivum 'Red Lion'temperature & humidity
Sempervivum 'Red Lion'
More about sempervivum 'red lion'
Ideal temperature for sempervivum 'red lion'
Aim for -20 to 27°C (-4 to 80°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 -20°C the damage starts — soft blackened patches, translucent leaves, sometimes overnight.
Cold tolerance & winter care
Sempervivum 'Red Lion' is frost-tender (USDA 4-8 (hardy outdoors; indoors keep cold and very bright), RHS H6). 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 sempervivum 'red lion'
Sempervivum 'Red Lion' sits happiest at around 30-50% relative humidity. Likes dry, well-ventilated air; humid, stagnant conditions encourage rot. Low to average indoor humidity with good airflow keeps the colourful rosettes firm and disease-free. 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.
Sempervivum 'Red Lion' temperature & humidity — frequently asked questions
What temperature is best for sempervivum 'red lion'?
Sempervivum 'Red Lion' grows best between -20 to 27°C (-4 to 80°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 sempervivum 'red lion' tolerate?
Sempervivum 'Red Lion' starts to suffer below roughly -20°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 sempervivum 'red lion' need?
Sempervivum 'Red Lion' prefers about 30-50% relative humidity. Likes dry, well-ventilated air; humid, stagnant conditions encourage rot. Low to average indoor humidity with good airflow keeps the colourful rosettes firm and disease-free.
How do I raise humidity for sempervivum 'red lion'?
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 sempervivum 'red lion' live outside?
Sempervivum 'Red Lion' is rated for USDA zone 4-8 (hardy outdoors; indoors keep cold and very bright) and RHS hardiness H6. Outside that range it must come indoors before the first frost — treat any outdoor stint as a summer holiday, not a permanent home.
More sempervivum 'red lion' care
In the UK? Keeping sempervivum 'red lion' warm in a UK home covers the radiator, single-glazing and heating-season humidity angle. Temperature and humidity are one piece. See the full sempervivum 'red lion' care guide, its cold-hardiness guide, and watering schedule — humidity and watering problems are easy to confuse.