Plant care
Pak Choi 'Joi Choi'temperature & humidity
Brassica rapa var. chinensis 'Joi Choi'
More about pak choi 'joi choi'
Ideal temperature for pak choi 'joi choi'
Pak Choi 'Joi Choi' is comfortable in any room a person is comfortable in, roughly 13-24°C (55-75°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 13°C growth pauses; cold beyond that pushes it into dormancy rather than killing it outright.
Cold tolerance & winter care
Pak Choi 'Joi Choi' is comparatively hardy (USDA Grown as a cool-season annual in zones 2-11, RHS H4). Within that range it tolerates a cold dormant spell outdoors; outside it, grow it in a container you can move under cover or overwinter in a cool but frost-free spot. Hardiness assumes an established plant in well-drained soil — a wet, cold root zone kills far more plants than cold air alone.
Humidity for pak choi 'joi choi'
Pak Choi 'Joi Choi' sits happiest at around Ambient outdoor relative humidity. No special humidity needs as a garden or container vegetable; adequate spacing and airflow limit downy mildew and basal rot in wet weather. 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.
Pak Choi 'Joi Choi' temperature & humidity — frequently asked questions
What temperature is best for pak choi 'joi choi'?
Pak Choi 'Joi Choi' grows best between 13-24°C (55-75°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 pak choi 'joi choi' tolerate?
Pak Choi 'Joi Choi' starts to suffer below roughly 13°C. It tolerates a cold dormant period within USDA Grown as a cool-season annual in zones 2-11, but a wet cold root zone is more dangerous than cold air.
What humidity does pak choi 'joi choi' need?
Pak Choi 'Joi Choi' prefers about Ambient outdoor relative humidity. No special humidity needs as a garden or container vegetable; adequate spacing and airflow limit downy mildew and basal rot in wet weather.
How do I raise humidity for pak choi 'joi choi'?
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 pak choi 'joi choi' live outside?
Pak Choi 'Joi Choi' is rated for USDA zone Grown as a cool-season annual in zones 2-11 and RHS hardiness H4. Within that range it can stay outdoors; outside it, grow it in a moveable container and protect the roots from a wet, cold winter.
More pak choi 'joi choi' care
In the UK? Keeping pak choi 'joi choi' warm in a UK home covers the radiator, single-glazing and heating-season humidity angle. Temperature and humidity are one piece. See the full pak choi 'joi choi' care guide, its cold-hardiness guide, and watering schedule — humidity and watering problems are easy to confuse.