Plant care
Tongue Water Trumpettemperature & humidity
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More about tongue water trumpet
Ideal temperature for tongue water trumpet
Temperature kills fewer tongue water trumpet 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 23–30°C (73–86°F) is fine; the spot you put the plant in matters more. Below roughly 23°C the damage starts — soft blackened patches, translucent leaves, sometimes overnight.
Cold tolerance & winter care
Tongue Water Trumpet is frost-tender (USDA 11–12 (aquatic or indoor-only), RHS H1b). 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 tongue water trumpet
Tongue Water Trumpet sits happiest at around 80–100% relative humidity. As an aquatic or semi-aquatic species, near-saturated humidity is required in emersed settings. Outdoors in tropical climates it tolerates high ambient humidity naturally. In indoor paludariums, maintain a closed or semi-closed humid environment. 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.
Tongue Water Trumpet temperature & humidity — frequently asked questions
What temperature is best for tongue water trumpet?
Tongue Water Trumpet grows best between 23–30°C (73–86°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 tongue water trumpet tolerate?
Tongue Water Trumpet starts to suffer below roughly 23°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 tongue water trumpet need?
Tongue Water Trumpet prefers about 80–100% relative humidity. As an aquatic or semi-aquatic species, near-saturated humidity is required in emersed settings. Outdoors in tropical climates it tolerates high ambient humidity naturally. In indoor paludariums, maintain a closed or semi-closed humid environment.
How do I raise humidity for tongue water 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 tongue water trumpet live outside?
Tongue Water Trumpet is rated for USDA zone 11–12 (aquatic or indoor-only) and RHS hardiness H1b. Outside that range it must come indoors before the first frost — treat any outdoor stint as a summer holiday, not a permanent home.
More tongue water trumpet care
In the UK? Keeping tongue water 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 tongue water trumpet care guide, its cold-hardiness guide, and watering schedule — humidity and watering problems are easy to confuse.