Cold hardiness & minimum temperature

Is Red Spider Lily (Lycoris radiata)cold hardy? Hardiness zone & min temp

Also called Red spider lily, Hurricane lily, Surprise lily, Equinox flower, Naked lily, Higanbana, Red magic lily.

More about red spider lily

About Red Spider Lily

Lycoris radiata · also called Red spider lily, Hurricane lily · flowering

Red spider lily (Lycoris radiata) is an autumn-flowering bulb in the amaryllis family, sending up leafless stems of fiery, spidery red blooms before its strap-like leaves appear. It is toxic to cats and dogs: every part contains the alkaloid lycorine, with the bulb most potent. Keep pets and children away and verify any exposure with your vet.

Cold limit: USDA USDA zones 6a-10b · RHS H3 (half-hardy; protect or lift in cold, wet-winter areas) (15-24°C)

Watch for — Erratic year-to-year blooming: Recently moved or divided bulbs and harsh winters that damage developing flower buds can cause skipped flowering for a season or two while plants re-establish.

What red spider lily's hardiness rating actually means

Red Spider Lily is half-hardy (RHS H3). 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 H3 means: Half-hardy — comes through mild UK winters outside but is killed by a hard freeze. On the US scale that maps to USDA USDA zones 6a-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 −5 to 1 °C — a light, short frost only. Red Spider Lily shrugs off cold nights but a real, sustained freeze will kill it.

Concretely, for red spider lily as it gets too cold:

Down to roughly about −5 to 1 °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 red spider lily go outside or overwinter — and where?

It can live outside year-round only in the mildest, most sheltered part of USDA USDA zones 6a-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 red spider lily can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H3 figure above.

Frost protection for borderline red spider lily

Red Spider 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.

Red Spider Lily hardiness — frequently asked questions

Is red spider lily cold hardy?

Red Spider Lily is half-hardy (RHS H3). 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 USDA zones 6a-10b (and sheltered UK gardens) red spider 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 red spider lily can survive?

Minimum survivable temperature is roughly about −5 to 1 °C — a light, short frost only. Red Spider Lily shrugs off cold nights but a real, sustained freeze will kill it.

What hardiness zone is red spider lily?

Red Spider Lily is rated USDA USDA zones 6a-10b and RHS H3 — Half-hardy — comes through mild UK winters outside but is killed by a hard freeze.

Can red spider lily survive winter outside?

It can live outside year-round only in the mildest, most sheltered part of USDA USDA zones 6a-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 red spider 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.