Cold hardiness & minimum temperature

Is Remusatia hookeriana (Remusatia hookeriana)cold hardy? Hardiness zone & min temp

Also called Hooker's remusatia.

More about remusatia hookeriana

About Remusatia hookeriana

Remusatia hookeriana · also called Hooker's remusatia · tropical

Remusatia hookeriana is a Himalayan tuberous aroid named for botanist J.D. Hooker. Like its viviparous cousin it produces handsome heart-shaped leaves from a dormant tuber and forms hooked bulbils for animal dispersal. It grows as an epiphyte or on rock in cool, moist montane forest, then dies back fully in the dry, cooler months.

Cold limit: USDA 9a-10 (Himalayan origin gives some cool tolerance; protect from frost and store tuber cool-dry) · RHS H2 (15-27°C)

Watch for — Tuber rot: Overwatering or cold, wet dormant storage rots the tuber. Use a gritty mix and keep nearly dry while dormant.

What remusatia hookeriana's hardiness rating actually means

Remusatia hookeriana 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 9a-10 (Himalayan origin gives some cool tolerance; protect from frost and store tuber cool-dry) — 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. Remusatia hookeriana shrugs off cold nights but a real, sustained freeze will kill it.

Concretely, for remusatia hookeriana 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 remusatia hookeriana go outside or overwinter — and where?

It can live outside year-round only in the mildest, most sheltered part of USDA 9a-10 (Himalayan origin gives some cool tolerance; protect from frost and store tuber cool-dry) 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 remusatia hookeriana 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 remusatia hookeriana

Remusatia hookeriana 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.

Remusatia hookeriana hardiness — frequently asked questions

Is remusatia hookeriana cold hardy?

Remusatia hookeriana 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 9a-10 (Himalayan origin gives some cool tolerance; protect from frost and store tuber cool-dry) (and sheltered UK gardens) remusatia hookeriana can stay out; in colder areas it must be lifted, brought in, or treated as a frost-tender plant.

What is the minimum temperature remusatia hookeriana can survive?

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

What hardiness zone is remusatia hookeriana?

Remusatia hookeriana is rated USDA 9a-10 (Himalayan origin gives some cool tolerance; protect from frost and store tuber cool-dry) and RHS H2 — Tender — survives a frost-free greenhouse or a very mild, sheltered spot.

Can remusatia hookeriana survive winter outside?

It can live outside year-round only in the mildest, most sheltered part of USDA 9a-10 (Himalayan origin gives some cool tolerance; protect from frost and store tuber cool-dry) 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 remusatia hookeriana 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.