UK hardiness
Is Kalanchoe Millotii hardy in the UK?
Kalanchoe millotii
More about kalanchoe millotii in the UK
Kalanchoe Millotii and the RHS hardiness rating
Kalanchoe Millotii is rated RHS H1c — warm temperate, meaning it withstands winter minimums of about 5 to 10°C. In practice that means it fine outdoors through most UK summers but must come in before the first frost. The RHS rating describes an absolute minimum temperature, not an average: a single hard frost below its band is what does the damage, so the question is always "what is the coldest night my garden gets?", not "what is a typical winter here?".
This follows the RHS plant hardiness rating system (H1a–H7), the UK standard. For the US growing-zone view, see the kalanchoe millotii USDA hardiness guide.
Does UK region change it?
Because kalanchoe millotii is frost-tender, UK region matters less than the simple rule: it does not stay outdoors over winter anywhere in the UK. Treat any time outside as a summer holiday — bring it back indoors once nights drop toward 10°C, well before the first frost, and acclimatise it over a week each way so the leaves do not shock.
Overwintering kalanchoe millotii in the UK
Overwintering kalanchoe millotii in the UK means bringing it in: a bright, frost-free room or a heated glasshouse, watered sparingly while growth slows. Do not leave it against cold glass or near an unheated porch. Move it back out only after the last spring frost has passed for your area.
Kalanchoe Millotii UK hardiness — frequently asked questions
Is kalanchoe millotii hardy in the UK?
Kalanchoe Millotii is rated RHS H1c (warm temperate, hardy to about 5 to 10°C). It is not winter-hardy anywhere in the UK and must be overwintered under cover.
Can kalanchoe millotii stay outside over winter in the UK?
No. Kalanchoe Millotii is frost-tender — a UK frost will kill it. Bring it indoors or into a frost-free greenhouse before the first autumn frost and return it outside only after the last spring frost.
What does RHS H1c mean?
RHS hardiness ratings run H1a (needs a heated glasshouse) to H7 (survives below -20°C). Kalanchoe Millotii's rating, H1c, means warm temperate — it tolerates winter minimums of about 5 to 10°C. The rating is an absolute minimum, not an average.
How do I overwinter kalanchoe millotii in the UK?
Overwintering kalanchoe millotii in the UK means bringing it in: a bright, frost-free room or a heated glasshouse, watered sparingly while growth slows. Do not leave it against cold glass or near an unheated porch. Move it back out only after the last spring frost has passed for your area.
Does UK region change whether kalanchoe millotii survives?
Because kalanchoe millotii is frost-tender, UK region matters less than the simple rule: it does not stay outdoors over winter anywhere in the UK. Treat any time outside as a summer holiday — bring it back indoors once nights drop toward 10°C, well before the first frost, and acclimatise it over a week each way so the leaves do not shock.
More kalanchoe millotii care
See the full kalanchoe millotii care guide, its temperature & humidity needs, and the US (USDA) hardiness version of this page.