Growli

Plant care

Rattlesnake Planttemperature & humidity

Goeppertia lancifolia (syn. Calathea lancifolia, Calathea insignis, Goeppertia insignis)

USDA 11-12Pet-safe

More about rattlesnake plant

Ideal temperature for rattlesnake plant

Aim for 18-24C (65-75F) on the thermostat and you've handled the easy part. The hard part is the half-metre around the plant: window glass that drops to near-freezing on a January night, a radiator pumping out hot dry air, a draught from an opened front door. Move the plant 30 cm and you've usually fixed the problem. Below roughly 18°C the damage starts — soft blackened patches, translucent leaves, sometimes overnight.

Cold tolerance & winter care

Rattlesnake Plant is frost-tender (USDA 11-12 (grown as a houseplant in all 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 rattlesnake plant

Rattlesnake Plant sits happiest at around 60% or higher relative humidity. A high-humidity plant; it browns and curls at the leaf edges in dry indoor air. Boost humidity with a pebble tray, a humidifier, or by grouping with other plants. Bathrooms and kitchens with good light often work well. Misting offers only brief relief and can encourage leaf spotting. 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.

Rattlesnake Plant temperature & humidity — frequently asked questions

What temperature is best for rattlesnake plant?

Rattlesnake Plant grows best between 18-24C (65-75F). 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 rattlesnake plant tolerate?

Rattlesnake Plant 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 rattlesnake plant need?

Rattlesnake Plant prefers about 60% or higher relative humidity. A high-humidity plant; it browns and curls at the leaf edges in dry indoor air. Boost humidity with a pebble tray, a humidifier, or by grouping with other plants. Bathrooms and kitchens with good light often work well. Misting offers only brief relief and can encourage leaf spotting.

How do I raise humidity for rattlesnake plant?

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 rattlesnake plant live outside?

Rattlesnake Plant is rated for USDA zone 11-12 (grown as a houseplant in all 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 rattlesnake plant care

In the UK? Keeping rattlesnake plant warm in a UK home covers the radiator, single-glazing and heating-season humidity angle. Temperature and humidity are one piece. See the full rattlesnake plant care guide, its cold-hardiness guide, and watering schedule — humidity and watering problems are easy to confuse.