Cold hardiness & minimum temperature

Is Persian Rosularia (Rosularia persica)cold hardy? Hardiness zone & min temp

Also called Persian Rosularia.

More about persian rosularia

About Persian Rosularia

Rosularia persica · also called Persian Rosularia · houseplant

A small, mat-forming Crassulaceae succulent native to rocky hillsides and cliff faces from eastern Turkey through Lebanon and into Iran. Its dense rosettes of fleshy, grey-green leaves and summer pink flower spikes make it a refined choice for rock gardens and alpine troughs — or as a bright-windowsill houseplant with minimal water needs.

Cold limit: USDA 5–9 · RHS H5 (5–27°C)

Watch for — Root rot: Excess moisture, especially in cool temperatures, quickly causes basal rot. Always use free-draining soil and pots with drainage holes; water sparingly in winter.

What persian rosularia's hardiness rating actually means

Yes — persian rosularia is genuinely cold hardy. Rated RHS H5 and USDA 5–9, it lives outdoors all year and needs winter cold rather than protection from it. Its RHS rating of H5 means: Hardy in most of the UK and in cold winters. On the US scale that maps to USDA 5–9 — 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 −15 to −10 °C. Persian Rosularia is built for winter — once established it takes hard frost and snow in its stride.

Concretely, for persian rosularia as it gets too cold:

It tolerates winter lows to about −15 to −10 °C once established.
Below its rated zone, the visible damage is browned or blackened top growth and, in the worst case, a killed crown or root.
First-year, newly planted, or container-grown specimens are noticeably less hardy than established garden plants — the roots are exposed.

Can persian rosularia go outside or overwinter — and where?

Plant it out within USDA 5–9 and it overwinters with little or no help.
It does not want to come indoors — a warm winter room actually weakens a hardy plant by denying it dormancy.
The real risks in its range are waterlogging, wind-rock on young plants, and a late hard frost on new growth — not ordinary winter cold.

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 persian rosularia can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H5 figure above.

Persian Rosularia hardiness — frequently asked questions

Is persian rosularia cold hardy?

Yes — persian rosularia is genuinely cold hardy. Rated RHS H5 and USDA 5–9, it lives outdoors all year and needs winter cold rather than protection from it. An outdoor plant. Persian Rosularia is hardy across USDA 5–9; it belongs in the ground or a frost-proof container, not on a windowsill, and many types actively need a cold winter to perform.

What is the minimum temperature persian rosularia can survive?

Minimum survivable temperature is roughly about −15 to −10 °C. Persian Rosularia is built for winter — once established it takes hard frost and snow in its stride.

What hardiness zone is persian rosularia?

Persian Rosularia is rated USDA 5–9 and RHS H5 — Hardy in most of the UK and in cold winters.

Can persian rosularia survive winter outside?

Plant it out within USDA 5–9 and it overwinters with little or no help. It does not want to come indoors — a warm winter room actually weakens a hardy plant by denying it dormancy. The real risks in its range are waterlogging, wind-rock on young plants, and a late hard frost on new growth — not ordinary winter cold.

What happens to persian rosularia below its minimum temperature?

It tolerates winter lows to about −15 to −10 °C once established. Below its rated zone, the visible damage is browned or blackened top growth and, in the worst case, a killed crown or root. First-year, newly planted, or container-grown specimens are noticeably less hardy than established garden plants — the roots are exposed.