Cold hardiness & minimum temperature

Is Ctenanthe Setosa 'Grey Star' (Ctenanthe setosa 'Grey Star')cold hardy? Hardiness zone & min temp

Also called Ctenanthe Grey Star, Never never plant.

More about ctenanthe setosa 'grey star'

About Ctenanthe Setosa 'Grey Star'

Ctenanthe setosa 'Grey Star' · also called Ctenanthe Grey Star, Never never plant · houseplant

Ctenanthe setosa 'Grey Star' is a clumping Brazilian prayer plant grown for long silvery-grey lances feathered with dark green herringbone banding and burgundy undersides. It folds its leaves upright at night. It wants warm, humid, draught-free air and bright indirect light, and sulks fast in dry or cold conditions, making it a fussy but rewarding foliage plant.

Cold limit: USDA 11-12 (indoor in most US homes) · RHS H1b (18-27°C)

What ctenanthe setosa 'grey star''s hardiness rating actually means

Ctenanthe Setosa 'Grey Star' 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 11-12 (indoor in most US homes) — 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). Ctenanthe Setosa 'Grey Star' has no frost tolerance at all — it is an indoor plant in any climate with a real winter.

Concretely, for ctenanthe setosa 'grey star' as it gets too cold:

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.

Can ctenanthe setosa 'grey star' go outside or overwinter — and where?

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.

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

Ctenanthe Setosa 'Grey Star' hardiness — frequently asked questions

Is ctenanthe setosa 'grey star' cold hardy?

Ctenanthe Setosa 'Grey Star' 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. Ctenanthe Setosa 'Grey Star' can only live outside year-round in genuinely frost-free climates (roughly USDA 11-12 (indoor in most US homes)); everywhere else it is a houseplant that summers out at most.

What is the minimum temperature ctenanthe setosa 'grey star' can survive?

What hardiness zone is ctenanthe setosa 'grey star'?

Ctenanthe Setosa 'Grey Star' is rated USDA 11-12 (indoor in most US homes) and RHS H1b — Sub-tropical — a normal warm home is fine, but it cannot go outside in a cool season.

Can ctenanthe setosa 'grey star' 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 ctenanthe setosa 'grey star' 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.