Cold hardiness & minimum temperature

Is Vandell's Rock Jasmine (Androsace vandellii)cold hardy? Hardiness zone & min temp

Also called Vandell's Rock Jasmine, Silver Rock Jasmine, Silky Androsace.

More about vandell's rock jasmine

About Vandell's Rock Jasmine

Androsace vandellii · also called Vandell's Rock Jasmine, Silver Rock Jasmine · flowering

Androsace vandellii (syn. Androsace tomentosa) is a specialist high-alpine cushion plant native to siliceous rock faces and crevices in the Alps, Apennines, Pyrenees, and Sierra Nevada above 2,000 m. It forms beautifully symmetrical, silver-grey cushions of tiny rosettes densely covered in star-shaped white hairs, bearing stemless white flowers with a yellow eye in April. It is one of the most exacting Androsace species in cultivation, demanding perfect drainage, sharp aeration, vertical planting in acidic gritty soil, and protection from winter wet — typically grown in an alpine house. Androsace is not listed on the ASPCA database; classified as mildly-toxic out of caution.

Cold limit: USDA 4-7 · RHS H5 (-25 to 18°C)

Watch for — Crown rot from overhead moisture: The most common cause of failure; any water pooling in the cushion, especially at low temperatures, leads to irreversible Botrytis or Pythium rot — plant in vertical crevices or at an angle, and shelter from rain under glass.

What vandell's rock jasmine's hardiness rating actually means

Yes — vandell's rock jasmine is genuinely cold hardy. Rated RHS H5 and USDA 4-7, 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 4-7 — 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. Vandell's Rock Jasmine is built for winter — once established it takes hard frost and snow in its stride.

Concretely, for vandell's rock jasmine 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 vandell's rock jasmine go outside or overwinter — and where?

Plant it out within USDA 4-7 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 vandell's rock jasmine can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H5 figure above.

Vandell's Rock Jasmine hardiness — frequently asked questions

Is vandell's rock jasmine cold hardy?

Yes — vandell's rock jasmine is genuinely cold hardy. Rated RHS H5 and USDA 4-7, it lives outdoors all year and needs winter cold rather than protection from it. An outdoor plant. Vandell's Rock Jasmine is hardy across USDA 4-7; 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 vandell's rock jasmine can survive?

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

What hardiness zone is vandell's rock jasmine?

Vandell's Rock Jasmine is rated USDA 4-7 and RHS H5 — Hardy in most of the UK and in cold winters.

Can vandell's rock jasmine survive winter outside?

Plant it out within USDA 4-7 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 vandell's rock jasmine 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.