Cold hardiness & minimum temperature

Is Agave shrevei (Agave shrevei)cold hardy? Hardiness zone & min temp

Also called Shreve's agave, Chihuahuan mescal.

More about agave shrevei

About Agave shrevei

Agave shrevei · also called Shreve's agave, Chihuahuan mescal · houseplant

Agave shrevei is a medium to large agave native to the rocky slopes of the Sierra Madre Occidental in Sonora, Chihuahua and Sinaloa, Mexico, where it has long been harvested for mescal. It forms an open rosette of broad grey-green to bluish leaves edged with prominent teeth and a stout terminal spine. Sun-loving and drought-hardy, it suits large pots and warm rock gardens.

Cold limit: USDA 8b-11 (hardy to roughly -7 to -9°C / 15 to 20°F when dry) · RHS H3 (10-32°C)

What agave shrevei's hardiness rating actually means

Agave shrevei 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 8b-11 (hardy to roughly -7 to -9°C / 15 to 20°F when 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 −5 to 1 °C — a light, short frost only. Agave shrevei shrugs off cold nights but a real, sustained freeze will kill it.

Concretely, for agave shrevei 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 agave shrevei go outside or overwinter — and where?

It can live outside year-round only in the mildest, most sheltered part of USDA 8b-11 (hardy to roughly -7 to -9°C / 15 to 20°F when 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 agave shrevei 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 agave shrevei

Agave shrevei 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.

Agave shrevei hardiness — frequently asked questions

Is agave shrevei cold hardy?

Agave shrevei 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 8b-11 (hardy to roughly -7 to -9°C / 15 to 20°F when dry) (and sheltered UK gardens) agave shrevei can stay out; in colder areas it must be lifted, brought in, or treated as a frost-tender plant.

What is the minimum temperature agave shrevei can survive?

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

What hardiness zone is agave shrevei?

Agave shrevei is rated USDA 8b-11 (hardy to roughly -7 to -9°C / 15 to 20°F when dry) and RHS H3 — Half-hardy — comes through mild UK winters outside but is killed by a hard freeze.

Can agave shrevei survive winter outside?

It can live outside year-round only in the mildest, most sheltered part of USDA 8b-11 (hardy to roughly -7 to -9°C / 15 to 20°F when 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 agave shrevei 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.