Cold hardiness & minimum temperature

Is Seyrig's Caudex Vine (Nymphostemma seyrigii)cold hardy? Hardiness zone & min temp

Also called Seyrig's Caudex Vine.

More about seyrig's caudex vine

About Seyrig's Caudex Vine

Nymphostemma seyrigii · also called Seyrig's Caudex Vine · houseplant

A rare Malagasy caudiciform vine from the Apocynaceae family (formerly placed in Asclepiadaceae), prized by collectors for its woody, swollen caudex base and twining seasonal stems. Native to Madagascar's dry forests, it demands excellent drainage, bright light, a warm dry winter rest, and infrequent summer watering — a specialist's plant.

Cold limit: USDA 10b–11 · RHS H1b (15–32°C)

Watch for — Caudex rot in dormancy: Any moisture at the caudex neck during the winter rest period rapidly triggers fungal rot. Keep completely dry and ensure excellent airflow around the base when temperatures drop.

What seyrig's caudex vine's hardiness rating actually means

Seyrig's Caudex Vine 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 10b–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 10 °C (sustained cold below this is damaging). Seyrig's Caudex Vine has no frost tolerance at all — it is an indoor plant in any climate with a real winter.

Concretely, for seyrig's caudex vine 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 seyrig's caudex vine 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 seyrig's caudex vine can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H1b figure above.

Seyrig's Caudex Vine hardiness — frequently asked questions

Is seyrig's caudex vine cold hardy?

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

What is the minimum temperature seyrig's caudex vine can survive?

What hardiness zone is seyrig's caudex vine?

Seyrig's Caudex Vine is rated USDA 10b–11 and RHS H1b — Sub-tropical — a normal warm home is fine, but it cannot go outside in a cool season.

Can seyrig's caudex vine 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 seyrig's caudex vine 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.