Growli

Plant care

Green Cotton Lavendertemperature & humidity

Santolina rosmarinifolia

RHS H5USDA 6-9Mildly toxic to pets

More about green cotton lavender

Ideal temperature for green cotton lavender

Green Cotton Lavender is comfortable in any room a person is comfortable in, roughly -15°C to 35°C (5°F to 95°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 -15°C growth pauses; cold beyond that pushes it into dormancy rather than killing it outright.

Cold tolerance & winter care

Green Cotton Lavender is comparatively hardy (USDA 6-9, 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 green cotton lavender

Green Cotton Lavender sits happiest at around Low relative humidity. Prefers dry, well-ventilated conditions typical of Mediterranean hillsides; high ambient humidity combined with wet soil dramatically increases fungal disease risk. 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.

Green Cotton Lavender temperature & humidity — frequently asked questions

What temperature is best for green cotton lavender?

Green Cotton Lavender grows best between -15°C to 35°C (5°F to 95°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 green cotton lavender tolerate?

Green Cotton Lavender starts to suffer below roughly -15°C. It tolerates a cold dormant period within USDA 6-9, but a wet cold root zone is more dangerous than cold air.

What humidity does green cotton lavender need?

Green Cotton Lavender prefers about Low relative humidity. Prefers dry, well-ventilated conditions typical of Mediterranean hillsides; high ambient humidity combined with wet soil dramatically increases fungal disease risk.

How do I raise humidity for green cotton lavender?

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 green cotton lavender live outside?

Green Cotton Lavender is rated for USDA zone 6-9 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 green cotton lavender care

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