Cold hardiness & minimum temperature

Is Marbled Earth Star (Cryptanthus beuckeri)cold hardy? Hardiness zone & min temp

Also called Marbled Earth Star, Beucke's Earth Star.

More about marbled earth star

About Marbled Earth Star

Cryptanthus beuckeri · also called Marbled Earth Star, Beucke's Earth Star · tropical

Cryptanthus beuckeri is a small terrestrial bromeliad endemic to the Atlantic Forest of Bahia and northern Espírito Santo, Brazil, recognised by its unusual petiolate (stalked), paddle-shaped leaves marbled in green, brown, and cream tones. The rosette is compact and rather upright compared with most flat-growing Cryptanthus, and it offsets freely from short stolons in the leaf axils. The most important care fact is that this species is more shade-tolerant than many in the genus, preferring dappled light to preserve its subtle marbled patterning without bleaching. The Cryptanthus genus (Earth Star) is listed as non-toxic to cats and dogs by the ASPCA.

Cold limit: USDA 10-12 (indoor in most climates) · RHS H1b (18-28°C)

What marbled earth star's hardiness rating actually means

Marbled Earth 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 10-12 (indoor in most climates) — 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). Marbled Earth Star has no frost tolerance at all — it is an indoor plant in any climate with a real winter.

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

Marbled Earth Star hardiness — frequently asked questions

Is marbled earth star cold hardy?

Marbled Earth 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. Marbled Earth Star can only live outside year-round in genuinely frost-free climates (roughly USDA 10-12 (indoor in most climates)); everywhere else it is a houseplant that summers out at most.

What is the minimum temperature marbled earth star can survive?

What hardiness zone is marbled earth star?

Marbled Earth Star is rated USDA 10-12 (indoor in most climates) and RHS H1b — Sub-tropical — a normal warm home is fine, but it cannot go outside in a cool season.

Can marbled earth 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 marbled earth 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.