Cold hardiness & minimum temperature

Is Moroccan Lavender (Lavandula maroccana)cold hardy? Hardiness zone & min temp

Also called Moroccan lavender, Atlas lavender.

More about moroccan lavender

About Moroccan Lavender

Lavandula maroccana · also called Moroccan lavender, Atlas lavender · herb

Moroccan lavender is an evergreen perennial shrub endemic to Morocco's High Atlas mountains and their western extensions, where it grows at altitudes up to 1,700 m in dry, rocky terrain; it is globally assessed as Vulnerable (VU) due to overharvesting and habitat degradation. It forms an upright, rather sprawling bush with pinnate leaves and produces compact spikes of fragrant dark violet flowers from late winter at low altitudes through to midsummer at elevation. This species requires well-drained soil and full sun, and while it tolerates moderate winter cold from its mountain origin, it is not suitable for gardens with prolonged frost or wet winters. According to the ASPCA, lavender (Lavandula) is toxic to cats, dogs, and horses.

Cold limit: USDA 8-11 · RHS H3 (-5 to 38°C)

Watch for — Root and crown rot: The most common problem in cultivation; even brief periods of waterlogged soil, particularly when combined with cool temperatures, rapidly kill the root system. Excellent drainage and restrained watering are the primary preventive measures.

What moroccan lavender's hardiness rating actually means

Moroccan Lavender 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 8-11 — 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 −5 to 1 °C — a light, short frost only. Moroccan Lavender shrugs off cold nights but a real, sustained freeze will kill it.

Concretely, for moroccan lavender 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 moroccan lavender go outside or overwinter — and where?

It can live outside year-round only in the mildest, most sheltered part of USDA 8-11 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 moroccan lavender 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 moroccan lavender

Moroccan Lavender 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.

Moroccan Lavender hardiness — frequently asked questions

Is moroccan lavender cold hardy?

Moroccan Lavender 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 8-11 (and sheltered UK gardens) moroccan lavender can stay out; in colder areas it must be lifted, brought in, or treated as a frost-tender plant.

What is the minimum temperature moroccan lavender can survive?

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

What hardiness zone is moroccan lavender?

Moroccan Lavender is rated USDA 8-11 and RHS H3 — Half-hardy — comes through mild UK winters outside but is killed by a hard freeze.

Can moroccan lavender survive winter outside?

It can live outside year-round only in the mildest, most sheltered part of USDA 8-11 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 moroccan lavender 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.