Plant care
Thick-stemmed Aichrysontemperature & humidity
Aichryson pachycaulon
More about thick-stemmed aichryson
Ideal temperature for thick-stemmed aichryson
Aim for 8–25°C (46–77°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 8°C the damage starts — soft blackened patches, translucent leaves, sometimes overnight.
Cold tolerance & winter care
Thick-stemmed Aichryson is frost-tender (USDA 9b–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 thick-stemmed aichryson
Thick-stemmed Aichryson sits happiest at around 40–60% relative humidity. Benefits from moderate humidity reflecting its cloud-forest origin. Average indoor conditions are adequate. Avoid very dry, heated air in winter, which can cause leaf-tip desiccation. 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.
Thick-stemmed Aichryson temperature & humidity — frequently asked questions
What temperature is best for thick-stemmed aichryson?
Thick-stemmed Aichryson grows best between 8–25°C (46–77°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 thick-stemmed aichryson tolerate?
Thick-stemmed Aichryson starts to suffer below roughly 8°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 thick-stemmed aichryson need?
Thick-stemmed Aichryson prefers about 40–60% relative humidity. Benefits from moderate humidity reflecting its cloud-forest origin. Average indoor conditions are adequate. Avoid very dry, heated air in winter, which can cause leaf-tip desiccation.
How do I raise humidity for thick-stemmed aichryson?
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 thick-stemmed aichryson live outside?
Thick-stemmed Aichryson is rated for USDA zone 9b–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 thick-stemmed aichryson care
In the UK? Keeping thick-stemmed aichryson warm in a UK home covers the radiator, single-glazing and heating-season humidity angle. Temperature and humidity are one piece. See the full thick-stemmed aichryson care guide, its cold-hardiness guide, and watering schedule — humidity and watering problems are easy to confuse.