Cold hardiness & minimum temperature

Is Hedge bindweed (Calystegia sepium)cold hardy? Hardiness zone & min temp

Also called Hedge bindweed, Bellbind, Rutland beauty, Wild morning glory, Great bindweed.

More about hedge bindweed

About Hedge bindweed

Calystegia sepium · also called Hedge bindweed, Bellbind · flowering

Hedge bindweed is a vigorous, rhizomatous native climber found across temperate regions of the UK, Europe, and North America. It produces large, trumpet-shaped white flowers from summer into autumn. Extremely invasive, it spreads rapidly via deep, brittle roots and should only be grown under strict containment. Not suitable for garden borders without physical root barriers.

Cold limit: USDA 3–9 · RHS H6 (-20 to 25°C)

What hedge bindweed's hardiness rating actually means

Yes — hedge bindweed is genuinely cold hardy. Rated RHS H6 and USDA 3–9, it lives outdoors all year and needs winter cold rather than protection from it. Its RHS rating of H6 means: Hardy throughout the UK and northern Europe. On the US scale that maps to USDA 3–9 — the zones where it can be left outdoors year-round.

New to these scales? The USDA hardiness zone map explained covers how the zone numbers work, and you can find your own zone with the zone finder.

Minimum temperature — and what happens below it

Minimum survivable temperature is roughly about −20 to −15 °C. Hedge bindweed is built for winter — once established it takes hard frost and snow in its stride.

Concretely, for hedge bindweed as it gets too cold:

It tolerates winter lows to about −20 to −15 °C once established.
Below its rated zone, the visible damage is browned or blackened top growth and, in the worst case, a killed crown or root.
First-year, newly planted, or container-grown specimens are noticeably less hardy than established garden plants — the roots are exposed.

Can hedge bindweed go outside or overwinter — and where?

Plant it out within USDA 3–9 and it overwinters with little or no help.
It does not want to come indoors — a warm winter room actually weakens a hardy plant by denying it dormancy.
The real risks in its range are waterlogging, wind-rock on young plants, and a late hard frost on new growth — not ordinary winter cold.

Work back from your local frost dates with the frost-date calculator: the last spring frost and first autumn frost are what really decide when hedge bindweed can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H6 figure above.

Hedge bindweed hardiness — frequently asked questions

Is hedge bindweed cold hardy?

Yes — hedge bindweed is genuinely cold hardy. Rated RHS H6 and USDA 3–9, it lives outdoors all year and needs winter cold rather than protection from it. An outdoor plant. Hedge bindweed is hardy across USDA 3–9; it belongs in the ground or a frost-proof container, not on a windowsill, and many types actively need a cold winter to perform.

What is the minimum temperature hedge bindweed can survive?

Minimum survivable temperature is roughly about −20 to −15 °C. Hedge bindweed is built for winter — once established it takes hard frost and snow in its stride.

What hardiness zone is hedge bindweed?

Hedge bindweed is rated USDA 3–9 and RHS H6 — Hardy throughout the UK and northern Europe.

Can hedge bindweed survive winter outside?

Plant it out within USDA 3–9 and it overwinters with little or no help. It does not want to come indoors — a warm winter room actually weakens a hardy plant by denying it dormancy. The real risks in its range are waterlogging, wind-rock on young plants, and a late hard frost on new growth — not ordinary winter cold.

What happens to hedge bindweed below its minimum temperature?

It tolerates winter lows to about −20 to −15 °C once established. Below its rated zone, the visible damage is browned or blackened top growth and, in the worst case, a killed crown or root. First-year, newly planted, or container-grown specimens are noticeably less hardy than established garden plants — the roots are exposed.