Plant care
Biting Porroglossumtemperature & humidity
Porroglossum mordax
More about biting porroglossum
Ideal temperature for biting porroglossum
Aim for 9–20 °C (48–68 °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 9°C the damage starts — soft blackened patches, translucent leaves, sometimes overnight.
Cold tolerance & winter care
Biting Porroglossum is frost-tender (USDA 10–11, RHS H1c). 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 biting porroglossum
Biting Porroglossum sits happiest at around 75–95% relative humidity. Very high humidity is essential for this Andean cloud-forest species. A closed terrarium, Wardian case, or cool greenhouse with regular misting maintains the necessary microclimate. Persistent low humidity causes rapid leaf drop and root failure. 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.
Biting Porroglossum temperature & humidity — frequently asked questions
What temperature is best for biting porroglossum?
Biting Porroglossum grows best between 9–20 °C (48–68 °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 biting porroglossum tolerate?
Biting Porroglossum starts to suffer below roughly 9°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 biting porroglossum need?
Biting Porroglossum prefers about 75–95% relative humidity. Very high humidity is essential for this Andean cloud-forest species. A closed terrarium, Wardian case, or cool greenhouse with regular misting maintains the necessary microclimate. Persistent low humidity causes rapid leaf drop and root failure.
How do I raise humidity for biting porroglossum?
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 biting porroglossum live outside?
Biting Porroglossum is rated for USDA zone 10–11 and RHS hardiness H1c. Outside that range it must come indoors before the first frost — treat any outdoor stint as a summer holiday, not a permanent home.
More biting porroglossum care
In the UK? Keeping biting porroglossum warm in a UK home covers the radiator, single-glazing and heating-season humidity angle. Temperature and humidity are one piece. See the full biting porroglossum care guide, its cold-hardiness guide, and watering schedule — humidity and watering problems are easy to confuse.