Cold hardiness & minimum temperature

Is Pelargonium 'Flower of Spring' (Pelargonium 'Flower of Spring')cold hardy? Hardiness zone & min temp

Also called Flower of Spring geranium, Silver-leaved bedding pelargonium.

More about pelargonium 'flower of spring'

About Pelargonium 'Flower of Spring'

Pelargonium 'Flower of Spring' · also called Flower of Spring geranium, Silver-leaved bedding pelargonium · flowering

A classic Victorian silver-variegated zonal pelargonium with grey-green leaves broadly margined in white and small single scarlet flowers. Long used as a foliage bedding plant for its bright, cool-toned leaves, it is robust and easy in pots and borders. Tender to frost, it wants full sun, gritty free-draining compost and a frost-free winter.

Cold limit: USDA 9-11 (tender; protect from frost) · RHS H1c (10-24°C)

What pelargonium 'flower of spring''s hardiness rating actually means

Pelargonium 'Flower of Spring' is not cold hardy. It is a tropical houseplant that dies if it is left out through frost — there is no zone where it overwinters outdoors in a UK or cold-US climate. Its RHS rating of H1c means: Warm-temperate — can summer outdoors but must come in well before the first frost. On the US scale that maps to USDA 9-11 (tender; protect from frost) — 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 5 °C (and never frost). Pelargonium 'Flower of Spring' has no frost tolerance at all — it is an indoor plant in any climate with a real winter.

Concretely, for pelargonium 'flower of spring' as it gets too cold:

Below about about 5 °C, growth stalls and the leaves start to show cold stress — dark, water-soaked, or yellowing patches.
A single light frost blackens the foliage; a hard freeze kills the whole plant, roots included, and it does not recover.
Even a cold, draughty windowsill or an unheated porch in winter can be enough to damage it permanently.

Can pelargonium 'flower of spring' go outside or overwinter — and where?

It can holiday outdoors in summer once nights are reliably above 5 °C, in shade or dappled light, hardened off gradually.
Bring it back indoors well before the first autumn frost — do not wait for a frost warning, move it when nights drop toward 10-12 °C.
It will never overwinter outside in a temperate climate; the indoors is its winter home, full stop.

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 'flower of spring' can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H1c figure above.

Pelargonium 'Flower of Spring' hardiness — frequently asked questions

Is pelargonium 'flower of spring' cold hardy?

Pelargonium 'Flower of Spring' is not cold hardy. It is a tropical houseplant that dies if it is left out through frost — there is no zone where it overwinters outdoors in a UK or cold-US climate. Indoor-only in almost every home. Pelargonium 'Flower of Spring' can only live outside year-round in genuinely frost-free climates (roughly USDA 9-11 (tender; protect from frost)); everywhere else it is a houseplant that summers out at most.

What is the minimum temperature pelargonium 'flower of spring' can survive?

Minimum survivable temperature is roughly about 5 °C (and never frost). Pelargonium 'Flower of Spring' has no frost tolerance at all — it is an indoor plant in any climate with a real winter.

What hardiness zone is pelargonium 'flower of spring'?

Pelargonium 'Flower of Spring' is rated USDA 9-11 (tender; protect from frost) and RHS H1c — Warm-temperate — can summer outdoors but must come in well before the first frost.

Can pelargonium 'flower of spring' survive winter outside?

It can holiday outdoors in summer once nights are reliably above 5 °C, in shade or dappled light, hardened off gradually. Bring it back indoors well before the first autumn frost — do not wait for a frost warning, move it when nights drop toward 10-12 °C. It will never overwinter outside in a temperate climate; the indoors is its winter home, full stop.

What happens to pelargonium 'flower of spring' below its minimum temperature?

Below about about 5 °C, growth stalls and the leaves start to show cold stress — dark, water-soaked, or yellowing patches. A single light frost blackens the foliage; a hard freeze kills the whole plant, roots included, and it does not recover. Even a cold, draughty windowsill or an unheated porch in winter can be enough to damage it permanently.