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Cold hardiness & minimum temperature

Is magic star stromanthe (Stromanthe sanguinea 'Magic Star')cold hardy? Hardiness zone & min temp

Also called magic star stromanthe, magic star calathea, magic star prayer plant.

More about magic star stromanthe

About magic star stromanthe

Stromanthe sanguinea 'Magic Star' · also called magic star stromanthe, magic star calathea · tropical

Stromanthe sanguinea 'Magic Star' is a striking Brazilian rainforest perennial with creamy-white, green, and magenta-splashed leaves and vivid red-purple undersides. It demands high humidity, bright indirect light, and consistently moist but not waterlogged soil. A rewarding statement plant for warm, humid indoor spaces such as bathrooms and kitchens.

Cold limit: USDA 10–12 · RHS H1b (18–27°C)

What magic star stromanthe's hardiness rating actually means

magic star stromanthe 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 H1b means: Sub-tropical — a normal warm home is fine, but it cannot go outside in a cool season. On the US scale that maps to USDA 10–12 — 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 10 °C (sustained cold below this is damaging). magic star stromanthe has no frost tolerance at all — it is an indoor plant in any climate with a real winter.

Concretely, for magic star stromanthe as it gets too cold:

Can magic star stromanthe go outside or overwinter — and where?

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 magic star stromanthe can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H1b figure above.

magic star stromanthe hardiness — frequently asked questions

Is magic star stromanthe cold hardy?

magic star stromanthe 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. magic star stromanthe can only live outside year-round in genuinely frost-free climates (roughly USDA 10–12); everywhere else it is a houseplant that summers out at most.

What is the minimum temperature magic star stromanthe can survive?

Minimum survivable temperature is roughly about 10 °C (sustained cold below this is damaging). magic star stromanthe has no frost tolerance at all — it is an indoor plant in any climate with a real winter.

What hardiness zone is magic star stromanthe?

magic star stromanthe is rated USDA 10–12 and RHS H1b — Sub-tropical — a normal warm home is fine, but it cannot go outside in a cool season.

Can magic star stromanthe survive winter outside?

It can holiday outdoors in summer once nights are reliably above 10 °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 magic star stromanthe below its minimum temperature?

Below about about 10 °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.

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