Cold hardiness & minimum temperature

Is Carrion Flower (Stapelia gigantea) (Stapelia gigantea)cold hardy? Hardiness zone & min temp

Also called Carrion flower, Starfish flower, Zulu giant, Carrion plant, Toad plant, Giant toad plant.

More about carrion flower (stapelia gigantea)

About Carrion Flower (Stapelia gigantea)

Stapelia gigantea · also called Carrion flower, Starfish flower · flowering

Stapelia gigantea, the carrion or starfish flower, is a clumping South African stem succulent famous for giant star-shaped blooms that smell of rotting meat to lure pollinating flies. Give it full sun to bright light, gritty fast-draining soil, and sparing water. ASPCA lists no toxic Stapelia; treat as low-risk but vet-verify.

Cold limit: USDA USDA zones 9-11 (Missouri Botanical Garden lists 9-10); grown as an indoor or greenhouse plant elsewhere and overwintered above 10 C / 50 F. (16-27 C ideal; do not go below ~10 C)

Watch for — Black stem and root rot: The most common cause of death, triggered by overwatering, poorly draining soil, or cold-and-wet winters. Stems turn black, mushy, and collapse at the base. Cut well above any rot, let cuttings callous, and replant in dry gritty mix; keep much drier going forward.

What carrion flower (stapelia gigantea)'s hardiness rating actually means

Carrion Flower (Stapelia gigantea) is half-hardy (RHS H2). It survives a mild winter outdoors in a sheltered spot, but a hard frost kills it — so in colder zones it is lifted, potted, or grown as a tender plant. Its RHS rating of H2 means: Tender — survives a frost-free greenhouse or a very mild, sheltered spot. On the US scale that maps to USDA USDA zones 9-11 (Missouri Botanical Garden lists 9-10); grown as an indoor or greenhouse plant elsewhere and overwintered above 10 C / 50 F. — 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 1 to 5 °C — tolerates cold but no real frost. Carrion Flower (Stapelia gigantea) shrugs off cold nights but a real, sustained freeze will kill it.

Concretely, for carrion flower (stapelia gigantea) as it gets too cold:

Down to roughly about 1 to 5 °C it copes, especially if dry and sheltered.
A sustained hard frost collapses the top growth; whether it returns depends on whether the roots, crown or tubers froze.
Wet cold is far more lethal than dry cold for this plant — soggy, frozen soil is the usual killer.

Can carrion flower (stapelia gigantea) go outside or overwinter — and where?

It can live outside year-round only in the mildest, most sheltered part of USDA USDA zones 9-11 (Missouri Botanical Garden lists 9-10); grown as an indoor or greenhouse plant elsewhere and overwintered above 10 C / 50 F. or a frost-free UK microclimate.
In colder zones, grow it in a pot you can move under cover, or lift its tubers/roots and store them frost-free over winter.
A south-facing wall, free-draining soil and a dry winter position can push it a full zone hardier than the books suggest.

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 carrion flower (stapelia gigantea) can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H2 figure above.

Frost protection for borderline carrion flower (stapelia gigantea)

Carrion Flower (Stapelia gigantea) is right on a hardiness edge in many gardens, so if you are pushing it, these measures buy it the margin it needs:

Mulch the crown or root zone deeply with bark, straw or leaf-mould before the first hard frost.
Move container plants against a warm wall or into an unheated but frost-free porch or greenhouse.
Fleece the top growth on the coldest nights, and keep it on the dry side — dry roots survive cold far better than wet ones.
Lift dahlia-type tubers or tender crowns after the first light frost blackens the foliage and store them somewhere cool but frost-free.

Carrion Flower (Stapelia gigantea) hardiness — frequently asked questions

Is carrion flower (stapelia gigantea) cold hardy?

Carrion Flower (Stapelia gigantea) is half-hardy (RHS H2). It survives a mild winter outdoors in a sheltered spot, but a hard frost kills it — so in colder zones it is lifted, potted, or grown as a tender plant. Borderline outdoors. In its mild end of USDA USDA zones 9-11 (Missouri Botanical Garden lists 9-10); grown as an indoor or greenhouse plant elsewhere and overwintered above 10 C / 50 F. (and sheltered UK gardens) carrion flower (stapelia gigantea) can stay out; in colder areas it must be lifted, brought in, or treated as a frost-tender plant.

What is the minimum temperature carrion flower (stapelia gigantea) can survive?

Minimum survivable temperature is roughly about 1 to 5 °C — tolerates cold but no real frost. Carrion Flower (Stapelia gigantea) shrugs off cold nights but a real, sustained freeze will kill it.

What hardiness zone is carrion flower (stapelia gigantea)?

Carrion Flower (Stapelia gigantea) is rated USDA USDA zones 9-11 (Missouri Botanical Garden lists 9-10); grown as an indoor or greenhouse plant elsewhere and overwintered above 10 C / 50 F. and RHS H2 — Tender — survives a frost-free greenhouse or a very mild, sheltered spot.

Can carrion flower (stapelia gigantea) survive winter outside?

It can live outside year-round only in the mildest, most sheltered part of USDA USDA zones 9-11 (Missouri Botanical Garden lists 9-10); grown as an indoor or greenhouse plant elsewhere and overwintered above 10 C / 50 F. or a frost-free UK microclimate. In colder zones, grow it in a pot you can move under cover, or lift its tubers/roots and store them frost-free over winter. A south-facing wall, free-draining soil and a dry winter position can push it a full zone hardier than the books suggest.

How do I protect carrion flower (stapelia gigantea) from frost?

Mulch the crown or root zone deeply with bark, straw or leaf-mould before the first hard frost. Move container plants against a warm wall or into an unheated but frost-free porch or greenhouse. Fleece the top growth on the coldest nights, and keep it on the dry side — dry roots survive cold far better than wet ones. Lift dahlia-type tubers or tender crowns after the first light frost blackens the foliage and store them somewhere cool but frost-free.