Cold hardiness & minimum temperature

Is Fingerroot Ginger (Curcuma comosa)cold hardy? Hardiness zone & min temp

Also called Wan Chak Motluk, Thai Ginger, Krachai.

More about fingerroot ginger

About Fingerroot Ginger

Curcuma comosa · also called Wan Chak Motluk, Thai Ginger · tropical

A Thai medicinal ginger with distinctive finger-like rhizomes and large, deep-green leaves with attractive purple midribs. Produces attractive pink-purple flower bracts in summer. Used extensively in Thai traditional medicine. An eye-catching tropical accent plant for warm gardens, conservatories, or large containers.

Cold limit: USDA 9-11 · RHS H1c (20-35°C)

Watch for — Winter rhizome rot: Excess moisture during dormancy is the primary killer. Keep rhizomes dry and frost-free between autumn and spring.

What fingerroot ginger's hardiness rating actually means

Fingerroot Ginger 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 9-11 — 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). Fingerroot Ginger has no frost tolerance at all — it is an indoor plant in any climate with a real winter.

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

Fingerroot Ginger hardiness — frequently asked questions

Is fingerroot ginger cold hardy?

Fingerroot Ginger 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. Fingerroot Ginger can only live outside year-round in genuinely frost-free climates (roughly USDA 9-11); everywhere else it is a houseplant that summers out at most.

What is the minimum temperature fingerroot ginger can survive?

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

What hardiness zone is fingerroot ginger?

Fingerroot Ginger is rated USDA 9-11 and RHS H1c — Warm-temperate — can summer outdoors but must come in well before the first frost.

Can fingerroot ginger 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 fingerroot ginger 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.