Cold hardiness & minimum temperature

Is Josephine's Lily (Brunsvigia josephinae)cold hardy? Hardiness zone & min temp

Also called Josephine's lily, Candelabra flower, Chandelier flower, Royal Brunswick lily.

More about josephine's lily

About Josephine's Lily

Brunsvigia josephinae · also called Josephine's lily, Candelabra flower · flowering

Brunsvigia josephinae is the largest and most majestic species in the genus, a deciduous bulbous perennial from the Western Cape of South Africa whose giant umbels of up to 60 vivid pink flowers can measure 60 cm across — one of the most spectacular autumn-blooming bulb flowers in the world. Like all Brunsvigia, it is hysteranthous: the flower scape emerges from bare ground in late summer, and broad strap-like leaves follow only after flowering ends, persisting through winter before dying away in spring. Established bulbs can take up to 12 years to first bloom, and any disturbance resets the clock — so the single most critical care rule is never to repot or divide without strong reason. All parts are toxic to pets due to Amaryllidaceae alkaloids.

Cold limit: USDA 9-11 · RHS H2 (5–30°C; frost-free above 5°C required in winter)

Watch for — Non-flowering despite maturity: Even well-grown bulbs can miss a year if summer drought was interrupted, if the bulb was moved, or if winter temperatures were insufficient to trigger dormancy correctly. Patience and strict adherence to the wet-winter, dry-summer cycle is essential.

What josephine's lily's hardiness rating actually means

Josephine's 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 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 1 to 5 °C — tolerates cold but no real frost. Josephine's Lily shrugs off cold nights but a real, sustained freeze will kill it.

Concretely, for josephine's 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 josephine's lily go outside or overwinter — and where?

It can live outside year-round only in the mildest, most sheltered part of USDA 9-11 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 josephine's 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 josephine's lily

Josephine's 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.

Josephine's Lily hardiness — frequently asked questions

Is josephine's lily cold hardy?

Josephine's 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 9-11 (and sheltered UK gardens) josephine's 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 josephine's lily can survive?

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

What hardiness zone is josephine's lily?

Josephine's Lily is rated USDA 9-11 and RHS H2 — Tender — survives a frost-free greenhouse or a very mild, sheltered spot.

Can josephine's lily survive winter outside?

It can live outside year-round only in the mildest, most sheltered part of USDA 9-11 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 josephine's 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.