Cold hardiness & minimum temperature

Is Stardust Ice Plant (Delosperma floribundum)cold hardy? Hardiness zone & min temp

Also called Stardust Delosperma, Pinkish Ice Plant, Floriferous Ice Plant.

More about stardust ice plant

About Stardust Ice Plant

Delosperma floribundum · also called Stardust Delosperma, Pinkish Ice Plant · flowering

Delosperma floribundum, commonly sold as 'Stardust', is a free-flowering South African ice plant bearing abundant pale pink to white flowers with a distinctive white centre star. It blooms profusely from late spring through autumn and forms a low, spreading carpet. Not individually ASPCA-listed; treat as mildly toxic as a precaution.

Cold limit: USDA 6–9 · RHS H5 (-10–35°C)

Watch for — Winter root rot: The primary cause of loss — poor drainage in cold, wet winters. Ensure gritty, free-draining soil or grow in raised beds.

What stardust ice plant's hardiness rating actually means

Yes — stardust ice plant is genuinely cold hardy. Rated RHS H5 and USDA 6–9, 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 6–9 — 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. Stardust Ice Plant is built for winter — once established it takes hard frost and snow in its stride.

Concretely, for stardust ice plant 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 stardust ice plant go outside or overwinter — and where?

Plant it out within USDA 6–9 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 stardust ice plant can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H5 figure above.

Stardust Ice Plant hardiness — frequently asked questions

Is stardust ice plant cold hardy?

Yes — stardust ice plant is genuinely cold hardy. Rated RHS H5 and USDA 6–9, it lives outdoors all year and needs winter cold rather than protection from it. An outdoor plant. Stardust Ice Plant is hardy across USDA 6–9; 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 stardust ice plant can survive?

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

What hardiness zone is stardust ice plant?

Stardust Ice Plant is rated USDA 6–9 and RHS H5 — Hardy in most of the UK and in cold winters.

Can stardust ice plant survive winter outside?

Plant it out within USDA 6–9 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 stardust ice plant 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.