Plant care
Night-scented stocktemperature & humidity
Matthiola longipetala
More about night-scented stock
Ideal temperature for night-scented stock
Night-scented stock is comfortable in any room a person is comfortable in, roughly 5–22°C (41–72°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 5°C growth pauses; cold beyond that pushes it into dormancy rather than killing it outright.
Cold tolerance & winter care
Night-scented stock is comparatively hardy (USDA Annual; sow in zones 2–10, RHS H5). 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 night-scented stock
Night-scented stock sits happiest at around 30–60% relative humidity. Prefers moderate to low humidity and good air flow. Excellent drainage is more important than humidity level. In persistently damp climates, grow in raised beds or on slopes to ensure drainage and prevent stem base rots. 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.
Night-scented stock temperature & humidity — frequently asked questions
What temperature is best for night-scented stock?
Night-scented stock grows best between 5–22°C (41–72°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 night-scented stock tolerate?
Night-scented stock starts to suffer below roughly 5°C. It tolerates a cold dormant period within USDA Annual; sow in zones 2–10, but a wet cold root zone is more dangerous than cold air.
What humidity does night-scented stock need?
Night-scented stock prefers about 30–60% relative humidity. Prefers moderate to low humidity and good air flow. Excellent drainage is more important than humidity level. In persistently damp climates, grow in raised beds or on slopes to ensure drainage and prevent stem base rots.
How do I raise humidity for night-scented stock?
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 night-scented stock live outside?
Night-scented stock is rated for USDA zone Annual; sow in zones 2–10 and RHS hardiness H5. 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 night-scented stock care
In the UK? Keeping night-scented stock warm in a UK home covers the radiator, single-glazing and heating-season humidity angle. Temperature and humidity are one piece. See the full night-scented stock care guide, its cold-hardiness guide, and watering schedule — humidity and watering problems are easy to confuse.