Cold hardiness & minimum temperature

Is Purple Passion Plant (Gynura aurantiaca)cold hardy? Hardiness zone & min temp

Also called purple passion plant, purple velvet plant, royal velvet plant.

More about purple passion plant

About Purple Passion Plant

Gynura aurantiaca · also called purple passion plant, purple velvet plant · houseplant

Gynura aurantiaca is a fast-growing tropical perennial from Indonesia, covered in dense velvety purple hairs that give the leaves an iridescent violet sheen. It needs bright indirect light to keep its vivid colour, grows vigorously in warm conditions, and is confirmed pet-safe by the ASPCA — an unusual combination for such a striking foliage plant.

Cold limit: USDA 10-12 · RHS H1b (15–24°C)

What purple passion plant's hardiness rating actually means

Purple Passion Plant 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). Purple Passion Plant has no frost tolerance at all — it is an indoor plant in any climate with a real winter.

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

Purple Passion Plant hardiness — frequently asked questions

Is purple passion plant cold hardy?

Purple Passion Plant 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. Purple Passion Plant 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 purple passion plant can survive?

What hardiness zone is purple passion plant?

Purple Passion Plant 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 purple passion plant 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 purple passion plant 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.