Cold hardiness & minimum temperature

Is Burchard's Caralluma (Caralluma burchardii)cold hardy? Hardiness zone & min temp

Also called Burchard's Caralluma, Canary Island Caralluma.

More about burchard's caralluma

About Burchard's Caralluma

Caralluma burchardii · also called Burchard's Caralluma, Canary Island Caralluma · houseplant

Caralluma burchardii is a rare succulent stapeliad native to the Canary Islands and North Africa, forming upright four-angled grey-green stems with small teeth along the ridges. Clusters of small, star-shaped, maroon-purple flowers with a carrion scent appear in summer. A striking collector's plant for warm, bright positions.

Cold limit: USDA 10-11 · RHS H1c (10–35°C)

What burchard's caralluma's hardiness rating actually means

Burchard's Caralluma 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 10-11 — 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). Burchard's Caralluma has no frost tolerance at all — it is an indoor plant in any climate with a real winter.

Concretely, for burchard's caralluma 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 burchard's caralluma 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 burchard's caralluma can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H1c figure above.

Burchard's Caralluma hardiness — frequently asked questions

Is burchard's caralluma cold hardy?

Burchard's Caralluma 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. Burchard's Caralluma can only live outside year-round in genuinely frost-free climates (roughly USDA 10-11); everywhere else it is a houseplant that summers out at most.

What is the minimum temperature burchard's caralluma can survive?

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

What hardiness zone is burchard's caralluma?

Burchard's Caralluma is rated USDA 10-11 and RHS H1c — Warm-temperate — can summer outdoors but must come in well before the first frost.

Can burchard's caralluma 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 burchard's caralluma 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.