Plant care
String of Turtlestemperature & humidity
Peperomia prostrata
More about string of turtles
Ideal temperature for string of turtles
Aim for 18-24°C (65-75°F) 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
String of Turtles is frost-tender (USDA 10-12 (indoors/outdoors only in frost-free climates), RHS H1b (min 10-15°C; can summer outdoors but needs warmth)). 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 string of turtles
String of Turtles sits happiest at around 40-60% relative humidity. It is comfortable at average indoor humidity but appreciates a slightly moister atmosphere around 40-60%, which keeps the small leaves plump. A pebble tray or occasional misting is usually enough; avoid constantly wet foliage, as still, soggy conditions invite fungal leaf spots and mushy stems. It also does well in a well-ventilated terrarium with sharp drainage. 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.
String of Turtles temperature & humidity — frequently asked questions
What temperature is best for string of turtles?
String of Turtles grows best between 18-24°C (65-75°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 string of turtles tolerate?
String of Turtles 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 string of turtles need?
String of Turtles prefers about 40-60% relative humidity. It is comfortable at average indoor humidity but appreciates a slightly moister atmosphere around 40-60%, which keeps the small leaves plump. A pebble tray or occasional misting is usually enough; avoid constantly wet foliage, as still, soggy conditions invite fungal leaf spots and mushy stems. It also does well in a well-ventilated terrarium with sharp drainage.
How do I raise humidity for string of turtles?
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 string of turtles live outside?
String of Turtles is rated for USDA zone 10-12 (indoors/outdoors only in frost-free climates) and RHS hardiness H1b (min 10-15°C; can summer outdoors but needs warmth). Outside that range it must come indoors before the first frost — treat any outdoor stint as a summer holiday, not a permanent home.
More string of turtles care
In the UK? Keeping string of turtles warm in a UK home covers the radiator, single-glazing and heating-season humidity angle. Temperature and humidity are one piece. See the full string of turtles care guide, its cold-hardiness guide, and watering schedule — humidity and watering problems are easy to confuse.