Cold hardiness & minimum temperature

Is Edge of Night Heliconia (Heliconia orthotricha)cold hardy? Hardiness zone & min temp

Also called Edge of Night, Hairy Heliconia.

More about edge of night heliconia

About Edge of Night Heliconia

Heliconia orthotricha · also called Edge of Night, Hairy Heliconia · tropical

Heliconia orthotricha is a bold tropical perennial from Central and South America, prized for its dramatically dark bracts edged in vivid color. It thrives in high heat and humidity with consistently moist soil. Not listed by the ASPCA, so treat as potentially toxic and keep away from pets.

Cold limit: USDA 10-12 (bring indoors below 15°C) · RHS H1b (18-30°C)

What edge of night heliconia's hardiness rating actually means

Edge of Night Heliconia 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 (bring indoors below 15°C) — 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). Edge of Night Heliconia has no frost tolerance at all — it is an indoor plant in any climate with a real winter.

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

Edge of Night Heliconia hardiness — frequently asked questions

Is edge of night heliconia cold hardy?

Edge of Night Heliconia 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. Edge of Night Heliconia can only live outside year-round in genuinely frost-free climates (roughly USDA 10-12 (bring indoors below 15°C)); everywhere else it is a houseplant that summers out at most.

What is the minimum temperature edge of night heliconia can survive?

What hardiness zone is edge of night heliconia?

Edge of Night Heliconia is rated USDA 10-12 (bring indoors below 15°C) and RHS H1b — Sub-tropical — a normal warm home is fine, but it cannot go outside in a cool season.

Can edge of night heliconia 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 edge of night heliconia 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.