Cold hardiness & minimum temperature

Is Purple Heart (Tradescantia pallida)cold hardy? Hardiness zone & min temp

Also called Purple Heart, Purple Queen, Purple Secretia, Setcreasea, Purple Spiderwort, Purple Wandering Jew.

More about purple heart

About Purple Heart

Tradescantia pallida · also called Purple Heart, Purple Queen · houseplant

Purple Heart (Tradescantia pallida) is a fast-growing trailing houseplant prized for vivid violet-purple foliage. Give it the brightest light you can for deepest colour, let the top inch of soil dry between waterings, and pinch to keep it bushy. The ASPCA classes the Tradescantia genus as toxic, so keep it away from pets.

Cold limit: USDA 10-11 (grow as a houseplant or summer annual in cooler zones; foliage is damaged below about 10°C / 50°F) (18-26°C)

What purple heart's hardiness rating actually means

Purple Heart 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 10-11 (grow as a houseplant or summer annual in cooler zones; foliage is damaged below about 10°C / 50°F) — 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). Purple Heart has no frost tolerance at all — it is an indoor plant in any climate with a real winter.

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

Purple Heart hardiness — frequently asked questions

Is purple heart cold hardy?

Purple Heart 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 Heart can only live outside year-round in genuinely frost-free climates (roughly USDA 10-11 (grow as a houseplant or summer annual in cooler zones; foliage is damaged below about 10°C / 50°F)); everywhere else it is a houseplant that summers out at most.

What is the minimum temperature purple heart can survive?

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

What hardiness zone is purple heart?

Purple Heart is rated USDA 10-11 (grow as a houseplant or summer annual in cooler zones; foliage is damaged below about 10°C / 50°F) and RHS H1c — Warm-temperate — can summer outdoors but must come in well before the first frost.

Can purple heart 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 purple heart 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.