Plant care
Shallottemperature & humidity
Allium cepa var. aggregatum
More about shallot
Ideal temperature for shallot
Temperature kills fewer shallot 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 13-24°C (55-75°F) is fine; the spot you put the plant in matters more. Below roughly 13°C growth pauses; cold beyond that pushes it into dormancy rather than killing it outright.
Cold tolerance & winter care
Shallot is comparatively hardy (USDA 4-9 (spring-planted; overwintered in milder zones), RHS H5 (sets planted late winter to early spring; some overwinter in mild areas)). 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 shallot
Shallot sits happiest at around 40-60% relative humidity. An outdoor crop unaffected by air humidity. A dry, sunny ripening period is important for curing the papery skins that give shallots their long shelf life. 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.
Shallot temperature & humidity — frequently asked questions
What temperature is best for shallot?
Shallot 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 shallot tolerate?
Shallot starts to suffer below roughly 13°C. It tolerates a cold dormant period within USDA 4-9 (spring-planted; overwintered in milder zones), but a wet cold root zone is more dangerous than cold air.
What humidity does shallot need?
Shallot prefers about 40-60% relative humidity. An outdoor crop unaffected by air humidity. A dry, sunny ripening period is important for curing the papery skins that give shallots their long shelf life.
How do I raise humidity for shallot?
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 shallot live outside?
Shallot is rated for USDA zone 4-9 (spring-planted; overwintered in milder zones) and RHS hardiness H5 (sets planted late winter to early spring; some overwinter in mild areas). 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 shallot care
In the UK? Keeping shallot warm in a UK home covers the radiator, single-glazing and heating-season humidity angle. Temperature and humidity are one piece. See the full shallot care guide, its cold-hardiness guide, and watering schedule — humidity and watering problems are easy to confuse.