Growli

Plant care

Western Sundewtemperature & humidity

Drosera occidentalis

RHS H2USDA 9-10Mildly toxic to pets

More about western sundew

Ideal temperature for western sundew

Western Sundew is comfortable in any room a person is comfortable in, roughly 5–25 °C (growing season) (41–77 °F (growing season)). The mistakes are micro-climates: a north-facing window on a frosty night, a south-facing windowsill in a summer heatwave, the standing draught between an opened kitchen door and the radiator behind it. Read the room around the plant, not the thermostat. Below roughly 5°C the damage starts — soft blackened patches, translucent leaves, sometimes overnight.

Cold tolerance & winter care

Western Sundew is frost-tender (USDA 9-10 (outdoor in Mediterranean-climate areas only), 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 western sundew

Western Sundew sits happiest at around 40–65% relative humidity. Moderate humidity during the growing season; terrarium conditions with stable 50–60% humidity work well and are beneficial for this small species, provided airflow prevents fungal issues. 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.

Western Sundew temperature & humidity — frequently asked questions

What temperature is best for western sundew?

Western Sundew grows best between 5–25 °C (growing season) (41–77 °F (growing season)). 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 western sundew tolerate?

Western Sundew starts to suffer below roughly 5°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 western sundew need?

Western Sundew prefers about 40–65% relative humidity. Moderate humidity during the growing season; terrarium conditions with stable 50–60% humidity work well and are beneficial for this small species, provided airflow prevents fungal issues.

How do I raise humidity for western sundew?

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 western sundew live outside?

Western Sundew is rated for USDA zone 9-10 (outdoor in Mediterranean-climate areas only) 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 western sundew care

In the UK? Keeping western sundew warm in a UK home covers the radiator, single-glazing and heating-season humidity angle. Temperature and humidity are one piece. See the full western sundew care guide, its cold-hardiness guide, and watering schedule — humidity and watering problems are easy to confuse.