Cold hardiness & minimum temperature

Is Pelargonium-Flowered Stork's Bill (Erodium pelargoniiflorum)cold hardy? Hardiness zone & min temp

Also called Pelargonium-Flowered Stork's Bill, Pelargonium Stork's Bill.

More about pelargonium-flowered stork's bill

About Pelargonium-Flowered Stork's Bill

Erodium pelargoniiflorum · also called Pelargonium-Flowered Stork's Bill, Pelargonium Stork's Bill · flowering

Erodium pelargoniiflorum is a woody-based perennial native to Turkey, forming a low mound of long-stalked, apple-green, heart-shaped leaves. From early summer onwards it bears clusters of white flowers in which the two upper petals are conspicuously spotted with purple, giving the appearance of a small pelargonium bloom. It requires full sun and sharply-drained, preferably limey soil; it is notably drought-tolerant and long-lived when drainage is adequate. Not documented as toxic to cats or dogs; classified as mildly-toxic as ASPCA data for this precise species is absent.

Cold limit: USDA 6-9 · RHS H5 (-12 to 28°C)

Watch for — Root rot from winter wet: The woody base is susceptible to Phytophthora and Pythium in waterlogged winter soil; always plant in a raised position with grit mulch at the crown.

What pelargonium-flowered stork's bill's hardiness rating actually means

Yes — pelargonium-flowered stork's bill is genuinely cold hardy. Rated RHS H5 and USDA 6-9, it lives outdoors all year and needs winter cold rather than protection from it. Its RHS rating of H5 means: Hardy in most of the UK and in cold winters. On the US scale that maps to USDA 6-9 — 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 −15 to −10 °C. Pelargonium-Flowered Stork's Bill is built for winter — once established it takes hard frost and snow in its stride.

Concretely, for pelargonium-flowered stork's bill as it gets too cold:

It tolerates winter lows to about −15 to −10 °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 pelargonium-flowered stork's bill go outside or overwinter — and where?

Plant it out within USDA 6-9 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 pelargonium-flowered stork's bill can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H5 figure above.

Pelargonium-Flowered Stork's Bill hardiness — frequently asked questions

Is pelargonium-flowered stork's bill cold hardy?

Yes — pelargonium-flowered stork's bill is genuinely cold hardy. Rated RHS H5 and USDA 6-9, it lives outdoors all year and needs winter cold rather than protection from it. An outdoor plant. Pelargonium-Flowered Stork's Bill is hardy across USDA 6-9; 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 pelargonium-flowered stork's bill can survive?

Minimum survivable temperature is roughly about −15 to −10 °C. Pelargonium-Flowered Stork's Bill is built for winter — once established it takes hard frost and snow in its stride.

What hardiness zone is pelargonium-flowered stork's bill?

Pelargonium-Flowered Stork's Bill is rated USDA 6-9 and RHS H5 — Hardy in most of the UK and in cold winters.

Can pelargonium-flowered stork's bill survive winter outside?

Plant it out within USDA 6-9 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 pelargonium-flowered stork's bill below its minimum temperature?

It tolerates winter lows to about −15 to −10 °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.