Cold hardiness & minimum temperature

Is Geranium sanguineum (Geranium sanguineum)cold hardy? Hardiness zone & min temp

Also called Bloody cranesbill.

More about geranium sanguineum

About Geranium sanguineum

Geranium sanguineum · also called Bloody cranesbill · flowering

Geranium sanguineum, bloody cranesbill, is a tough, compact hardy geranium forming a dense mound of deeply cut dark-green leaves studded with magenta-pink, saucer-shaped flowers through summer. Its foliage often reddens in autumn. Drought-tolerant once established and happy in poor, well-drained soil, it makes excellent low ground cover for sunny banks and edges.

Cold limit: USDA 3-8 · RHS H7 (-34 to 30°C)

Watch for — Crown rot in wet ground: Waterlogged or heavy clay soil rots the rootstock over winter. Improve drainage with grit, plant slightly proud, and never let it sit wet.

What geranium sanguineum's hardiness rating actually means

Yes — geranium sanguineum is genuinely cold hardy. Rated RHS H7 and USDA 3-8, it lives outdoors all year and needs winter cold rather than protection from it. Its RHS rating of H7 means: Hardy in the severest European continental winters. On the US scale that maps to USDA 3-8 — 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 below about −20 °C. Geranium sanguineum is built for winter — once established it takes hard frost and snow in its stride.

Concretely, for geranium sanguineum as it gets too cold:

It tolerates winter lows to about −20 °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 geranium sanguineum go outside or overwinter — and where?

Plant it out within USDA 3-8 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 geranium sanguineum can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H7 figure above.

Geranium sanguineum hardiness — frequently asked questions

Is geranium sanguineum cold hardy?

Yes — geranium sanguineum is genuinely cold hardy. Rated RHS H7 and USDA 3-8, it lives outdoors all year and needs winter cold rather than protection from it. An outdoor plant. Geranium sanguineum is hardy across USDA 3-8; 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 geranium sanguineum can survive?

Minimum survivable temperature is roughly below about −20 °C. Geranium sanguineum is built for winter — once established it takes hard frost and snow in its stride.

What hardiness zone is geranium sanguineum?

Geranium sanguineum is rated USDA 3-8 and RHS H7 — Hardy in the severest European continental winters.

Can geranium sanguineum survive winter outside?

Plant it out within USDA 3-8 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 geranium sanguineum below its minimum temperature?

It tolerates winter lows to about −20 °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.