Cold hardiness & minimum temperature

Is Green's Ginger Lily (Hedychium greenii)cold hardy? Hardiness zone & min temp

Also called Green's ginger lily, red butterfly ginger, red ginger lily.

More about green's ginger lily

About Green's Ginger Lily

Hedychium greenii · also called Green's ginger lily, red butterfly ginger · tropical

Hedychium greenii is a clump-forming rhizomatous perennial native to Bhutan and Arunachal Pradesh, India, prized for its deep olive-green leaves with striking red-flushed undersides and dense spikes of vivid orange-red flowers from midsummer into autumn. It thrives in moist, humus-rich soil in a sheltered, sunny or part-shaded position, and produces plantlets on spent flower stalks rather than viable seed — the key propagation quirk. In frost-prone climates, rhizomes must be lifted and stored frost-free in winter or protected under deep mulch. The ASPCA lists multiple Hedychium species as non-toxic; this species is considered non-toxic to cats and dogs.

Cold limit: USDA 8b-10b · RHS H2 (15–30°C (active growth); minimum 5°C (dormant rhizome))

Watch for — Rhizome rot in winter: Overwatering or failure to reduce irrigation during dormancy allows cold, wet soil to rot rhizomes; lift and store frost-free or apply a deep mulch and cut back watering sharply in autumn.

What green's ginger lily's hardiness rating actually means

Green's Ginger Lily is half-hardy (RHS H2). It survives a mild winter outdoors in a sheltered spot, but a hard frost kills it — so in colder zones it is lifted, potted, or grown as a tender plant. Its RHS rating of H2 means: Tender — survives a frost-free greenhouse or a very mild, sheltered spot. On the US scale that maps to USDA 8b-10b — 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 1 to 5 °C — tolerates cold but no real frost. Green's Ginger Lily shrugs off cold nights but a real, sustained freeze will kill it.

Concretely, for green's ginger lily as it gets too cold:

Down to roughly about 1 to 5 °C it copes, especially if dry and sheltered.
A sustained hard frost collapses the top growth; whether it returns depends on whether the roots, crown or tubers froze.
Wet cold is far more lethal than dry cold for this plant — soggy, frozen soil is the usual killer.

Can green's ginger lily go outside or overwinter — and where?

It can live outside year-round only in the mildest, most sheltered part of USDA 8b-10b or a frost-free UK microclimate.
In colder zones, grow it in a pot you can move under cover, or lift its tubers/roots and store them frost-free over winter.
A south-facing wall, free-draining soil and a dry winter position can push it a full zone hardier than the books suggest.

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 green's ginger lily can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H2 figure above.

Frost protection for borderline green's ginger lily

Green's Ginger Lily is right on a hardiness edge in many gardens, so if you are pushing it, these measures buy it the margin it needs:

Mulch the crown or root zone deeply with bark, straw or leaf-mould before the first hard frost.
Move container plants against a warm wall or into an unheated but frost-free porch or greenhouse.
Fleece the top growth on the coldest nights, and keep it on the dry side — dry roots survive cold far better than wet ones.
Lift dahlia-type tubers or tender crowns after the first light frost blackens the foliage and store them somewhere cool but frost-free.

Green's Ginger Lily hardiness — frequently asked questions

Is green's ginger lily cold hardy?

Green's Ginger Lily is half-hardy (RHS H2). It survives a mild winter outdoors in a sheltered spot, but a hard frost kills it — so in colder zones it is lifted, potted, or grown as a tender plant. Borderline outdoors. In its mild end of USDA 8b-10b (and sheltered UK gardens) green's ginger lily can stay out; in colder areas it must be lifted, brought in, or treated as a frost-tender plant.

What is the minimum temperature green's ginger lily can survive?

Minimum survivable temperature is roughly about 1 to 5 °C — tolerates cold but no real frost. Green's Ginger Lily shrugs off cold nights but a real, sustained freeze will kill it.

What hardiness zone is green's ginger lily?

Green's Ginger Lily is rated USDA 8b-10b and RHS H2 — Tender — survives a frost-free greenhouse or a very mild, sheltered spot.

Can green's ginger lily survive winter outside?

It can live outside year-round only in the mildest, most sheltered part of USDA 8b-10b or a frost-free UK microclimate. In colder zones, grow it in a pot you can move under cover, or lift its tubers/roots and store them frost-free over winter. A south-facing wall, free-draining soil and a dry winter position can push it a full zone hardier than the books suggest.

How do I protect green's ginger lily from frost?

Mulch the crown or root zone deeply with bark, straw or leaf-mould before the first hard frost. Move container plants against a warm wall or into an unheated but frost-free porch or greenhouse. Fleece the top growth on the coldest nights, and keep it on the dry side — dry roots survive cold far better than wet ones. Lift dahlia-type tubers or tender crowns after the first light frost blackens the foliage and store them somewhere cool but frost-free.