Cold hardiness & minimum temperature

Is Cylindrical Rock Jasmine (Androsace cylindrica)cold hardy? Hardiness zone & min temp

Also called Cylindrical Rock Jasmine, Cylindrical Androsace.

More about cylindrical rock jasmine

About Cylindrical Rock Jasmine

Androsace cylindrica · also called Cylindrical Rock Jasmine, Cylindrical Androsace · flowering

Cylindrical Rock Jasmine is a rare, specialist alpine perennial endemic to the Pyrenees, forming extraordinarily tight, elongated cylindrical rosettes that build into dense domed cushions. White flowers with a yellow eye appear in spring. One of the most challenging Androsace species in cultivation, it is grown almost exclusively by specialist alpine enthusiasts in an alpine house or tufa garden.

Cold limit: USDA 3–5 · RHS H7 (-25°C to 15°C)

Watch for — Irreversible cushion rot: Any moisture reaching the rosette centres, particularly in cool or humid conditions, rapidly triggers lethal fungal rot. Prevention through alpine house cultivation, near-dry winter management, and vertical tufa planting is the only reliable approach; affected sections cannot be saved.

What cylindrical rock jasmine's hardiness rating actually means

Yes — cylindrical rock jasmine is genuinely cold hardy. Rated RHS H7 and USDA 3–5, it lives outdoors all year and needs winter cold rather than protection from it. Its RHS rating of H7 means: Hardy in the severest European continental winters. On the US scale that maps to USDA 3–5 — 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 below about −20 °C. Cylindrical Rock Jasmine is built for winter — once established it takes hard frost and snow in its stride.

Concretely, for cylindrical rock jasmine as it gets too cold:

It tolerates winter lows to about −20 °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 cylindrical rock jasmine go outside or overwinter — and where?

Plant it out within USDA 3–5 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 cylindrical rock jasmine can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H7 figure above.

Cylindrical Rock Jasmine hardiness — frequently asked questions

Is cylindrical rock jasmine cold hardy?

Yes — cylindrical rock jasmine is genuinely cold hardy. Rated RHS H7 and USDA 3–5, it lives outdoors all year and needs winter cold rather than protection from it. An outdoor plant. Cylindrical Rock Jasmine is hardy across USDA 3–5; 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 cylindrical rock jasmine can survive?

Minimum survivable temperature is roughly below about −20 °C. Cylindrical Rock Jasmine is built for winter — once established it takes hard frost and snow in its stride.

What hardiness zone is cylindrical rock jasmine?

Cylindrical Rock Jasmine is rated USDA 3–5 and RHS H7 — Hardy in the severest European continental winters.

Can cylindrical rock jasmine survive winter outside?

Plant it out within USDA 3–5 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 cylindrical rock jasmine below its minimum temperature?

It tolerates winter lows to about −20 °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.