Cold hardiness & minimum temperature

Is Striped Amaryllis (Hippeastrum vittatum)cold hardy? Hardiness zone & min temp

Also called Banded Amaryllis, Striped Hippeastrum, Peruvian Lily.

More about striped amaryllis

About Striped Amaryllis

Hippeastrum vittatum · also called Banded Amaryllis, Striped Hippeastrum · flowering

Hippeastrum vittatum is a South American bulb from the Andes producing large white or pale pink flowers striped with bold red or crimson veins in winter or spring. One of the original species used to breed modern hybrid amaryllis. Popular as a forced indoor bulb. Toxic to cats, dogs, and horses due to lycorine and alkaloids concentrated in the bulb.

Cold limit: USDA 8–10 (outdoor); indoor-only in colder climates · RHS H2 (13–27°C (dormancy at 10–13°C))

What striped amaryllis's hardiness rating actually means

Striped Amaryllis 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 8–10 (outdoor); indoor-only in colder climates — 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. Striped Amaryllis shrugs off cold nights but a real, sustained freeze will kill it.

Concretely, for striped amaryllis 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 striped amaryllis go outside or overwinter — and where?

It can live outside year-round only in the mildest, most sheltered part of USDA 8–10 (outdoor); indoor-only in colder climates 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 striped amaryllis 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 striped amaryllis

Striped Amaryllis 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.

Striped Amaryllis hardiness — frequently asked questions

Is striped amaryllis cold hardy?

Striped Amaryllis 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 8–10 (outdoor); indoor-only in colder climates (and sheltered UK gardens) striped amaryllis can stay out; in colder areas it must be lifted, brought in, or treated as a frost-tender plant.

What is the minimum temperature striped amaryllis can survive?

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

What hardiness zone is striped amaryllis?

Striped Amaryllis is rated USDA 8–10 (outdoor); indoor-only in colder climates and RHS H2 — Tender — survives a frost-free greenhouse or a very mild, sheltered spot.

Can striped amaryllis survive winter outside?

It can live outside year-round only in the mildest, most sheltered part of USDA 8–10 (outdoor); indoor-only in colder climates 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 striped amaryllis 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.