Cold hardiness & minimum temperature

Is Hedgerow Cranesbill (Geranium pyrenaicum)cold hardy? Hardiness zone & min temp

Also called Hedgerow Cranesbill, Mountain Cranesbill, Pyrenean Cranesbill.

More about hedgerow cranesbill

About Hedgerow Cranesbill

Geranium pyrenaicum · also called Hedgerow Cranesbill, Mountain Cranesbill · flowering

Geranium pyrenaicum is a clump-forming, semi-evergreen herbaceous perennial native to southern Europe and western Asia, now widely naturalised in the UK and northern Europe along roadsides, hedgerows, meadows and open woodland edges. Unlike most of the annual cranesbills in this group, it returns reliably year after year and self-seeds freely around the parent plant, producing a long succession of small purplish-pink flowers from late spring through to early autumn. It is undemanding, tolerating a wide range of soils in full sun to partial shade. True cranesbill Geranium species are not listed as toxic to pets by the ASPCA, and this species is considered non-toxic to cats and dogs.

Cold limit: USDA 5-9 · RHS H6 (-20 to 25°C)

What hedgerow cranesbill's hardiness rating actually means

Yes — hedgerow cranesbill is genuinely cold hardy. Rated RHS H6 and USDA 5-9, 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 5-9 — 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. Hedgerow Cranesbill is built for winter — once established it takes hard frost and snow in its stride.

Concretely, for hedgerow cranesbill 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 hedgerow cranesbill go outside or overwinter — and where?

Plant it out within USDA 5-9 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 hedgerow cranesbill can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H6 figure above.

Hedgerow Cranesbill hardiness — frequently asked questions

Is hedgerow cranesbill cold hardy?

Yes — hedgerow cranesbill is genuinely cold hardy. Rated RHS H6 and USDA 5-9, it lives outdoors all year and needs winter cold rather than protection from it. An outdoor plant. Hedgerow Cranesbill is hardy across USDA 5-9; 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 hedgerow cranesbill can survive?

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

What hardiness zone is hedgerow cranesbill?

Hedgerow Cranesbill is rated USDA 5-9 and RHS H6 — Hardy throughout the UK and northern Europe.

Can hedgerow cranesbill survive winter outside?

Plant it out within USDA 5-9 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 hedgerow cranesbill 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.