Cold hardiness & minimum temperature

Is Antigonon leptopus (Antigonon leptopus)cold hardy? Hardiness zone & min temp

Also called coral vine, Mexican creeper, queen's wreath.

More about antigonon leptopus

About Antigonon leptopus

Antigonon leptopus · also called coral vine, Mexican creeper · tropical

Antigonon leptopus, coral vine, is a vigorous tender tendril climber from Mexico smothered in sprays of bright pink (sometimes white) heart-shaped flowers through the warm months. It climbs fast by tendrils, thrives in heat and full sun, and is drought-tolerant once established, but is frost-tender and can be invasive in tropical and subtropical regions.

Cold limit: USDA 8-11 (root-hardy where mild; frost-tender top growth) · RHS H1c (15 to 35°C)

Watch for — Frost dieback: Top growth is killed by frost; in marginal areas the tuberous roots may resprout in spring. Mulch the crown over winter and cut away dead growth as new shoots appear.

What antigonon leptopus's hardiness rating actually means

Antigonon leptopus 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 8-11 (root-hardy where mild; frost-tender top growth) — 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). Antigonon leptopus has no frost tolerance at all — it is an indoor plant in any climate with a real winter.

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

Antigonon leptopus hardiness — frequently asked questions

Is antigonon leptopus cold hardy?

Antigonon leptopus 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. Antigonon leptopus can only live outside year-round in genuinely frost-free climates (roughly USDA 8-11 (root-hardy where mild; frost-tender top growth)); everywhere else it is a houseplant that summers out at most.

What is the minimum temperature antigonon leptopus can survive?

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

What hardiness zone is antigonon leptopus?

Antigonon leptopus is rated USDA 8-11 (root-hardy where mild; frost-tender top growth) and RHS H1c — Warm-temperate — can summer outdoors but must come in well before the first frost.

Can antigonon leptopus 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 antigonon leptopus 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.