Cold hardiness & minimum temperature

Is Cambodian Sonerila (Sonerila cambodiana)cold hardy? Hardiness zone & min temp

Also called Cambodian Sonerila.

More about cambodian sonerila

About Cambodian Sonerila

Sonerila cambodiana · also called Cambodian Sonerila · tropical

Cambodian Sonerila is a rare tropical herb endemic to the humid forests of Cambodia and adjacent Indochina, prized among collectors for its richly patterned leaves with silver or pale green markings and delicate pink blooms. It demands terrarium-level humidity and steady warmth, making it a specialist plant for experienced growers.

Cold limit: USDA 12 · RHS H1a (19–28°C)

What cambodian sonerila's hardiness rating actually means

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

Concretely, for cambodian sonerila 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 cambodian sonerila 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 cambodian sonerila can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H1a figure above.

Cambodian Sonerila hardiness — frequently asked questions

Is cambodian sonerila cold hardy?

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

What is the minimum temperature cambodian sonerila can survive?

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

What hardiness zone is cambodian sonerila?

Cambodian Sonerila is rated USDA 12 and RHS H1a — Tropical — needs a heated room or greenhouse; no frost tolerance whatsoever.

Can cambodian sonerila 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 cambodian sonerila 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.