Plant care
large-flowered butterworttemperature & humidity
Pinguicula grandiflora
More about large-flowered butterwort
Ideal temperature for large-flowered butterwort
Temperature kills fewer large-flowered butterwort 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 2–18°C growing season; tolerates −15°C in winter dormancy (35–65°F growing season; tolerates 5°F when dormant) is fine; the spot you put the plant in matters more. Below roughly 2°C growth pauses; cold beyond that pushes it into dormancy rather than killing it outright.
Cold tolerance & winter care
large-flowered butterwort is comparatively hardy (USDA 5-8, RHS H6). Within that range it tolerates a cold dormant spell outdoors; outside it, grow it in a container you can move under cover or overwinter in a cool but frost-free spot. Hardiness assumes an established plant in well-drained soil — a wet, cold root zone kills far more plants than cold air alone.
Humidity for large-flowered butterwort
large-flowered butterwort sits happiest at around 50–80% relative humidity. Being a cool-temperate alpine plant, it prefers moderately high humidity with good air movement. In dry indoor environments, place on a pebble tray with water. It dislikes dry centrally heated air and performs best when grown cool and moist, mimicking its native Atlantic highland habitat. 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.
large-flowered butterwort temperature & humidity — frequently asked questions
What temperature is best for large-flowered butterwort?
large-flowered butterwort grows best between 2–18°C growing season; tolerates −15°C in winter dormancy (35–65°F growing season; tolerates 5°F when dormant). 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 large-flowered butterwort tolerate?
large-flowered butterwort starts to suffer below roughly 2°C. It tolerates a cold dormant period within USDA 5-8, but a wet cold root zone is more dangerous than cold air.
What humidity does large-flowered butterwort need?
large-flowered butterwort prefers about 50–80% relative humidity. Being a cool-temperate alpine plant, it prefers moderately high humidity with good air movement. In dry indoor environments, place on a pebble tray with water. It dislikes dry centrally heated air and performs best when grown cool and moist, mimicking its native Atlantic highland habitat.
How do I raise humidity for large-flowered butterwort?
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 large-flowered butterwort live outside?
large-flowered butterwort is rated for USDA zone 5-8 and RHS hardiness H6. Within that range it can stay outdoors; outside it, grow it in a moveable container and protect the roots from a wet, cold winter.
More large-flowered butterwort care
In the UK? Keeping large-flowered butterwort warm in a UK home covers the radiator, single-glazing and heating-season humidity angle. Temperature and humidity are one piece. See the full large-flowered butterwort care guide, its cold-hardiness guide, and watering schedule — humidity and watering problems are easy to confuse.