Cold hardiness & minimum temperature

Is Malabar Quisqualis (Quisqualis malabarica)cold hardy? Hardiness zone & min temp

Also called Malabar Quisqualis, Malabar Rangoon Creeper.

More about malabar quisqualis

About Malabar Quisqualis

Quisqualis malabarica · also called Malabar Quisqualis, Malabar Rangoon Creeper · tropical

Malabar Quisqualis is a vigorous climbing shrub endemic to the Western Ghats of Kerala, India. It bears oblong leaves and reddish, fragrant flowers in terminal cymes, closely related to the Rangoon Creeper. Best grown on a trellis or pergola in full tropical sun with well-drained fertile soil and regular water. Not frost-hardy.

Cold limit: USDA 10–12 · RHS H1b (18–35°C)

Watch for — Root rot in poor drainage: Waterlogged soil causes rapid root rot, particularly in cooler temperatures. Plant in raised beds or add coarse grit to heavy soils to ensure rapid drainage after rain.

What malabar quisqualis's hardiness rating actually means

Malabar Quisqualis 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 10–12 — 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). Malabar Quisqualis has no frost tolerance at all — it is an indoor plant in any climate with a real winter.

Concretely, for malabar quisqualis 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 malabar quisqualis 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 malabar quisqualis can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H1b figure above.

Malabar Quisqualis hardiness — frequently asked questions

Is malabar quisqualis cold hardy?

Malabar Quisqualis 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. Malabar Quisqualis can only live outside year-round in genuinely frost-free climates (roughly USDA 10–12); everywhere else it is a houseplant that summers out at most.

What is the minimum temperature malabar quisqualis can survive?

What hardiness zone is malabar quisqualis?

Malabar Quisqualis is rated USDA 10–12 and RHS H1b — Sub-tropical — a normal warm home is fine, but it cannot go outside in a cool season.

Can malabar quisqualis 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 malabar quisqualis 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.