Cold hardiness & minimum temperature

Is Pelargonium graveolens 'Attar of Roses' (Pelargonium graveolens 'Attar of Roses')cold hardy? Hardiness zone & min temp

Also called Attar of Roses geranium, Rose-scented pelargonium Attar of Roses.

More about pelargonium graveolens 'attar of roses'

About Pelargonium graveolens 'Attar of Roses'

Pelargonium graveolens 'Attar of Roses' · also called Attar of Roses geranium, Rose-scented pelargonium Attar of Roses · herb

'Attar of Roses' is a rose-scented geranium prized for the intense, sweet rose fragrance released when its soft, lobed leaves are brushed. A vigorous South African Pelargonium, it grows as a bushy tender perennial used for potpourri, flavouring and essential oil. It loves bright sun, well-drained gritty soil and dislikes wet roots and frost.

Cold limit: USDA 9-11 (overwinter indoors or frost-free below zone 9) · RHS H2 (10-24°C)

What pelargonium graveolens 'attar of roses''s hardiness rating actually means

Pelargonium graveolens 'Attar of Roses' 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 9-11 (overwinter indoors or frost-free below zone 9) — 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. Pelargonium graveolens 'Attar of Roses' shrugs off cold nights but a real, sustained freeze will kill it.

Concretely, for pelargonium graveolens 'attar of roses' 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 pelargonium graveolens 'attar of roses' go outside or overwinter — and where?

It can live outside year-round only in the mildest, most sheltered part of USDA 9-11 (overwinter indoors or frost-free below zone 9) 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 pelargonium graveolens 'attar of roses' 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 pelargonium graveolens 'attar of roses'

Pelargonium graveolens 'Attar of Roses' 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.

Pelargonium graveolens 'Attar of Roses' hardiness — frequently asked questions

Is pelargonium graveolens 'attar of roses' cold hardy?

Pelargonium graveolens 'Attar of Roses' 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 9-11 (overwinter indoors or frost-free below zone 9) (and sheltered UK gardens) pelargonium graveolens 'attar of roses' can stay out; in colder areas it must be lifted, brought in, or treated as a frost-tender plant.

What is the minimum temperature pelargonium graveolens 'attar of roses' can survive?

What hardiness zone is pelargonium graveolens 'attar of roses'?

Pelargonium graveolens 'Attar of Roses' is rated USDA 9-11 (overwinter indoors or frost-free below zone 9) and RHS H2 — Tender — survives a frost-free greenhouse or a very mild, sheltered spot.

Can pelargonium graveolens 'attar of roses' survive winter outside?

It can live outside year-round only in the mildest, most sheltered part of USDA 9-11 (overwinter indoors or frost-free below zone 9) 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 pelargonium graveolens 'attar of roses' 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.