Plant care
White Arrow Arumtemperature & humidity
Peltandra sagittifolia
More about white arrow arum
Ideal temperature for white arrow arum
Temperature kills fewer white arrow arum 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 5–35°C (41–95°F) is fine; the spot you put the plant in matters more. Below roughly 5°C growth pauses; cold beyond that pushes it into dormancy rather than killing it outright.
Cold tolerance & winter care
White Arrow Arum is comparatively hardy (USDA 5-9, RHS H5). 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 white arrow arum
White Arrow Arum sits happiest at around 60–100% relative humidity. Naturally grows in humid wetland environments. High ambient humidity suits it perfectly; low humidity is tolerated only if roots remain waterlogged. 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.
White Arrow Arum temperature & humidity — frequently asked questions
What temperature is best for white arrow arum?
White Arrow Arum grows best between 5–35°C (41–95°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 white arrow arum tolerate?
White Arrow Arum starts to suffer below roughly 5°C. It tolerates a cold dormant period within USDA 5-9, but a wet cold root zone is more dangerous than cold air.
What humidity does white arrow arum need?
White Arrow Arum prefers about 60–100% relative humidity. Naturally grows in humid wetland environments. High ambient humidity suits it perfectly; low humidity is tolerated only if roots remain waterlogged.
How do I raise humidity for white arrow arum?
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 white arrow arum live outside?
White Arrow Arum is rated for USDA zone 5-9 and RHS hardiness H5. 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 white arrow arum care
In the UK? Keeping white arrow arum warm in a UK home covers the radiator, single-glazing and heating-season humidity angle. Temperature and humidity are one piece. See the full white arrow arum care guide, its cold-hardiness guide, and watering schedule — humidity and watering problems are easy to confuse.