Growli

Plant care

Giant Chalk Dudleyatemperature & humidity

Dudleya brittonii

RHS H3USDA 9–11Mildly toxic to pets

More about giant chalk dudleya

Ideal temperature for giant chalk dudleya

Aim for 7–27°C (45–80°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 7°C growth pauses; cold beyond that pushes it into dormancy rather than killing it outright.

Cold tolerance & winter care

Giant Chalk Dudleya is comparatively hardy (USDA 9–11, RHS H3). 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 giant chalk dudleya

Giant Chalk Dudleya sits happiest at around 20–40% relative humidity. Prefers low humidity typical of Mediterranean and coastal desert climates. High indoor humidity leads to fungal issues. Avoid placing near humidifiers or in bathrooms. 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.

Giant Chalk Dudleya temperature & humidity — frequently asked questions

What temperature is best for giant chalk dudleya?

Giant Chalk Dudleya grows best between 7–27°C (45–80°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 giant chalk dudleya tolerate?

Giant Chalk Dudleya starts to suffer below roughly 7°C. It tolerates a cold dormant period within USDA 9–11, but a wet cold root zone is more dangerous than cold air.

What humidity does giant chalk dudleya need?

Giant Chalk Dudleya prefers about 20–40% relative humidity. Prefers low humidity typical of Mediterranean and coastal desert climates. High indoor humidity leads to fungal issues. Avoid placing near humidifiers or in bathrooms.

How do I raise humidity for giant chalk dudleya?

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 giant chalk dudleya live outside?

Giant Chalk Dudleya is rated for USDA zone 9–11 and RHS hardiness H3. 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 giant chalk dudleya care

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