Growli

UK hardiness

Is Glory Bower hardy in the UK?

Clerodendrum splendens

RHS H1cUSDA 10-12Mildly toxic to pets

More about glory bower in the UK

Glory Bower and the RHS hardiness rating

Glory Bower 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 glory bower USDA hardiness guide.

Does UK region change it?

Because glory bower 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 glory bower in the UK

Overwintering glory bower 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.

Glory Bower UK hardiness — frequently asked questions

Is glory bower hardy in the UK?

Glory Bower 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 glory bower stay outside over winter in the UK?

No. Glory Bower 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). Glory Bower'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 glory bower in the UK?

Overwintering glory bower 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 glory bower survives?

Because glory bower 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 glory bower care

See the full glory bower care guide, its temperature & humidity needs, and the US (USDA) hardiness version of this page.