Cold hardiness & minimum temperature

Is Didier's Angraecum (Angraecum didieri)cold hardy? Hardiness zone & min temp

Also called Didier's Angraecum.

More about didier's angraecum

About Didier's Angraecum

Angraecum didieri · also called Didier's Angraecum · tropical

A miniature star orchid endemic to Madagascar's humid evergreen forests at 600–1,500 m, Didier's Angraecum bears proportionally enormous, pure-white star-shaped flowers with a long spur, producing an intense spicy-citrus night fragrance. Despite its small size it is tough and relatively rewarding, blooming from April through June and often again in autumn, but is extremely sensitive to repotting.

Cold limit: USDA 10-12 · RHS H1a (16–35°C)

What didier's angraecum's hardiness rating actually means

Didier's Angraecum 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 H1a means: Tropical — needs a heated room or greenhouse; no frost tolerance whatsoever. 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 above about 15 °C (warm, never cold). Didier's Angraecum has no frost tolerance at all — it is an indoor plant in any climate with a real winter.

Concretely, for didier's angraecum as it gets too cold:

Below about above about 15 °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 didier's angraecum go outside or overwinter — and where?

It can holiday outdoors in summer once nights are reliably above above 15 °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 didier's angraecum can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H1a figure above.

Didier's Angraecum hardiness — frequently asked questions

Is didier's angraecum cold hardy?

Didier's Angraecum 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. Didier's Angraecum 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 didier's angraecum can survive?

Minimum survivable temperature is roughly above about 15 °C (warm, never cold). Didier's Angraecum has no frost tolerance at all — it is an indoor plant in any climate with a real winter.

What hardiness zone is didier's angraecum?

Didier's Angraecum is rated USDA 10-12 and RHS H1a — Tropical — needs a heated room or greenhouse; no frost tolerance whatsoever.

Can didier's angraecum survive winter outside?

It can holiday outdoors in summer once nights are reliably above above 15 °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 didier's angraecum below its minimum temperature?

Below about above about 15 °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.