Plant care
Kauritemperature & humidity
Agathis australis
More about kauri
Ideal temperature for kauri
Temperature kills fewer kauri 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°C to 32°C (41°F to 90°F) is fine; the spot you put the plant in matters more. Below roughly 5°C the damage starts — soft blackened patches, translucent leaves, sometimes overnight.
Cold tolerance & winter care
Kauri is frost-tender (USDA 9-11, 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 kauri
Kauri sits happiest at around 60–90% relative humidity. Requires high humidity, reflecting its native warm-temperate rainforest environment. Under glass, provide good ventilation alongside humidity; stagnant moist air encourages fungal disease. Stand on damp gravel trays or use foliage misting in dry heated interiors. Poor humidity results in tip browning and poor growth. 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.
Kauri temperature & humidity — frequently asked questions
What temperature is best for kauri?
Kauri grows best between 5°C to 32°C (41°F to 90°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 kauri tolerate?
Kauri 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 kauri need?
Kauri prefers about 60–90% relative humidity. Requires high humidity, reflecting its native warm-temperate rainforest environment. Under glass, provide good ventilation alongside humidity; stagnant moist air encourages fungal disease. Stand on damp gravel trays or use foliage misting in dry heated interiors. Poor humidity results in tip browning and poor growth.
How do I raise humidity for kauri?
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 kauri live outside?
Kauri is rated for USDA zone 9-11 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 kauri care
In the UK? Keeping kauri warm in a UK home covers the radiator, single-glazing and heating-season humidity angle. Temperature and humidity are one piece. See the full kauri care guide, its cold-hardiness guide, and watering schedule — humidity and watering problems are easy to confuse.