Cold hardiness & minimum temperature

Is Cotyledon Papillaris (Cotyledon papillaris)cold hardy? Hardiness zone & min temp

Also called finger cotyledon, necklace vine cotyledon.

More about cotyledon papillaris

About Cotyledon Papillaris

Cotyledon papillaris · also called finger cotyledon, necklace vine cotyledon · houseplant

Cotyledon papillaris is a compact, dwarf South African succulent with small, plump, finger-like green leaves often tipped and edged in red, borne on short branching stems. It stays low and shrubby and bears tubular orange-red flowers. Easy in bright light with very sharp drainage. As a Cotyledon it is toxic to pets, containing cardiac glycosides.

Cold limit: USDA 9-11 (indoor or container in colder US zones) · RHS H2 (10-27°C)

Watch for — Leaf drop: Sudden leaf drop often follows overwatering or abrupt changes in light or temperature. Keep watering consistent and conditions stable to prevent the fleshy leaves from dropping.

What cotyledon papillaris's hardiness rating actually means

Cotyledon Papillaris 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 9-11 (indoor or container in colder US zones) — 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. Cotyledon Papillaris shrugs off cold nights but a real, sustained freeze will kill it.

Concretely, for cotyledon papillaris 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 cotyledon papillaris go outside or overwinter — and where?

It can live outside year-round only in the mildest, most sheltered part of USDA 9-11 (indoor or container in colder US zones) 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 cotyledon papillaris 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 cotyledon papillaris

Cotyledon Papillaris 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.

Cotyledon Papillaris hardiness — frequently asked questions

Is cotyledon papillaris cold hardy?

Cotyledon Papillaris 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 9-11 (indoor or container in colder US zones) (and sheltered UK gardens) cotyledon papillaris can stay out; in colder areas it must be lifted, brought in, or treated as a frost-tender plant.

What is the minimum temperature cotyledon papillaris can survive?

Minimum survivable temperature is roughly about 1 to 5 °C — tolerates cold but no real frost. Cotyledon Papillaris shrugs off cold nights but a real, sustained freeze will kill it.

What hardiness zone is cotyledon papillaris?

Cotyledon Papillaris is rated USDA 9-11 (indoor or container in colder US zones) and RHS H2 — Tender — survives a frost-free greenhouse or a very mild, sheltered spot.

Can cotyledon papillaris survive winter outside?

It can live outside year-round only in the mildest, most sheltered part of USDA 9-11 (indoor or container in colder US zones) 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 cotyledon papillaris 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.