Plant care
New Guinea Impatienstemperature & humidity
Impatiens hawkeri
More about new guinea impatiens
Ideal temperature for new guinea impatiens
New Guinea Impatiens is comfortable in any room a person is comfortable in, roughly 16-27°C (60-80°F). 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 16°C the damage starts — soft blackened patches, translucent leaves, sometimes overnight.
Cold tolerance & winter care
New Guinea Impatiens is frost-tender (USDA 10-11 (grown as an annual in most US zones), 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 new guinea impatiens
New Guinea Impatiens sits happiest at around 50-70% relative humidity. Prefers moderate to high humidity; in hot, dry air the leaf edges brown and flowering slows. Even outdoor moisture in the soil matters more than misting. 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.
New Guinea Impatiens temperature & humidity — frequently asked questions
What temperature is best for new guinea impatiens?
New Guinea Impatiens grows best between 16-27°C (60-80°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 new guinea impatiens tolerate?
New Guinea Impatiens starts to suffer below roughly 16°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 new guinea impatiens need?
New Guinea Impatiens prefers about 50-70% relative humidity. Prefers moderate to high humidity; in hot, dry air the leaf edges brown and flowering slows. Even outdoor moisture in the soil matters more than misting.
How do I raise humidity for new guinea impatiens?
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 new guinea impatiens live outside?
New Guinea Impatiens is rated for USDA zone 10-11 (grown as an annual in most US zones) 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 new guinea impatiens care
In the UK? Keeping new guinea impatiens warm in a UK home covers the radiator, single-glazing and heating-season humidity angle. Temperature and humidity are one piece. See the full new guinea impatiens care guide, its cold-hardiness guide, and watering schedule — humidity and watering problems are easy to confuse.