Plant care
Golden Trumpettemperature & humidity
Allamanda cathartica
More about golden trumpet
Ideal temperature for golden trumpet
Golden Trumpet is comfortable in any room a person is comfortable in, roughly 18-27 C (65-80 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 18°C the damage starts — soft blackened patches, translucent leaves, sometimes overnight.
Cold tolerance & winter care
Golden Trumpet is frost-tender (USDA USDA 10-11 (frost-tender; grown as a container or conservatory plant and overwintered indoors in cooler zones), RHS undefined). 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 golden trumpet
Golden Trumpet sits happiest at around 50-70% relative humidity. Prefers moderate to high humidity (50% or above; 60-70% is ideal). In dry indoor air, use a pebble humidity tray, group plants, or run a humidifier to prevent leaf-edge browning and discourage spider mites. 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.
Golden Trumpet temperature & humidity — frequently asked questions
What temperature is best for golden trumpet?
Golden Trumpet grows best between 18-27 C (65-80 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 golden trumpet tolerate?
Golden Trumpet starts to suffer below roughly 18°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 golden trumpet need?
Golden Trumpet prefers about 50-70% relative humidity. Prefers moderate to high humidity (50% or above; 60-70% is ideal). In dry indoor air, use a pebble humidity tray, group plants, or run a humidifier to prevent leaf-edge browning and discourage spider mites.
How do I raise humidity for golden trumpet?
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 golden trumpet live outside?
Golden Trumpet is rated for USDA zone USDA 10-11 (frost-tender; grown as a container or conservatory plant and overwintered indoors in cooler zones). Outside that range it must come indoors before the first frost — treat any outdoor stint as a summer holiday, not a permanent home.
More golden trumpet care
In the UK? Keeping golden trumpet warm in a UK home covers the radiator, single-glazing and heating-season humidity angle. Temperature and humidity are one piece. See the full golden trumpet care guide, its cold-hardiness guide, and watering schedule — humidity and watering problems are easy to confuse.