Growli

Plant care

Woolly Lavendertemperature & humidity

Lavandula lanata

RHS H4USDA 7-9Toxic to pets

More about woolly lavender

Ideal temperature for woolly lavender

Aim for -10°C to 38°C (14°F to 100°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 -10°C growth pauses; cold beyond that pushes it into dormancy rather than killing it outright.

Cold tolerance & winter care

Woolly Lavender is comparatively hardy (USDA 7-9, 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 woolly lavender

Woolly Lavender sits happiest at around Low (20–45% RH) relative humidity. Very sensitive to high humidity and summer rain; the woolly indumentum that repels drought can trap fungal spores, so ensure excellent ventilation. 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.

Woolly Lavender temperature & humidity — frequently asked questions

What temperature is best for woolly lavender?

Woolly Lavender grows best between -10°C to 38°C (14°F to 100°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 woolly lavender tolerate?

Woolly Lavender starts to suffer below roughly -10°C. It tolerates a cold dormant period within USDA 7-9, but a wet cold root zone is more dangerous than cold air.

What humidity does woolly lavender need?

Woolly Lavender prefers about Low (20–45% RH) relative humidity. Very sensitive to high humidity and summer rain; the woolly indumentum that repels drought can trap fungal spores, so ensure excellent ventilation.

How do I raise humidity for woolly 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 woolly lavender live outside?

Woolly Lavender is rated for USDA zone 7-9 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 woolly lavender care

In the UK? Keeping woolly 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 woolly lavender care guide, its cold-hardiness guide, and watering schedule — humidity and watering problems are easy to confuse.