Cold hardiness & minimum temperature

Is Anise-scented Sage (Salvia guaranitica)cold hardy? Hardiness zone & min temp

Also called Anise-scented Sage, Blue Anise Sage, Brazilian Sage.

More about anise-scented sage

About Anise-scented Sage

Salvia guaranitica · also called Anise-scented Sage, Blue Anise Sage · flowering

Anise-scented sage is a vigorous, tuberous-rooted subshrub native to South America (Brazil, Paraguay, Uruguay, and Argentina), prized for its deep cobalt-blue flowers held in near-black calyxes that bloom from late summer until hard frost. Brushing the wrinkled, hairy leaves releases a pleasant anise fragrance that gives the plant its common name. In the UK and cooler US zones it is grown as a half-hardy perennial — the tuberous roots can be lifted and stored like dahlias, or the whole plant overwintered in a frost-free space. The Salvia genus is listed as non-toxic to cats, dogs, and horses by the ASPCA.

Cold limit: USDA 7-10 · RHS H3 (-5 to 35°C)

Watch for — Tuberous root rot in cold wet soils: Tuberous roots left in cold, wet ground over winter in USDA zone 7 or UK H3 conditions often rot; lift after first frost, dry for 2–3 days, and store in dry vermiculite at 7–10°C until spring.

What anise-scented sage's hardiness rating actually means

Anise-scented Sage 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 7-10 — 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. Anise-scented Sage shrugs off cold nights but a real, sustained freeze will kill it.

Concretely, for anise-scented sage 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 anise-scented sage go outside or overwinter — and where?

It can live outside year-round only in the mildest, most sheltered part of USDA 7-10 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 anise-scented sage 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 anise-scented sage

Anise-scented Sage 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.

Anise-scented Sage hardiness — frequently asked questions

Is anise-scented sage cold hardy?

Anise-scented Sage 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 7-10 (and sheltered UK gardens) anise-scented sage can stay out; in colder areas it must be lifted, brought in, or treated as a frost-tender plant.

What is the minimum temperature anise-scented sage can survive?

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

What hardiness zone is anise-scented sage?

Anise-scented Sage is rated USDA 7-10 and RHS H3 — Half-hardy — comes through mild UK winters outside but is killed by a hard freeze.

Can anise-scented sage survive winter outside?

It can live outside year-round only in the mildest, most sheltered part of USDA 7-10 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 anise-scented sage 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.