Cold hardiness & minimum temperature

Is Brunthal's Ice Plant (Delosperma brunnthaleri)cold hardy? Hardiness zone & min temp

Also called Brunthal's Ice Plant, Hardy Ice Plant.

More about brunthal's ice plant

About Brunthal's Ice Plant

Delosperma brunnthaleri · also called Brunthal's Ice Plant, Hardy Ice Plant · houseplant

Delosperma brunnthaleri is a low-growing, mat-forming Aizoaceae succulent from South Africa producing vivid, daisy-like flowers over a long season. Like other hardy ice plants, it is more cold-tolerant than most mesembs. Suitable for sunny windowsills, rock gardens, or as ground cover in frost-free areas. Not ASPCA-listed; treat cautiously around pets.

Cold limit: USDA 6-11 · RHS H4 (-5 to 30°C)

Watch for — Root rot in wet winters: Plants in poorly draining soil or pots are susceptible to winter rot. Improve drainage and reduce watering significantly in cold months.

What brunthal's ice plant's hardiness rating actually means

Yes — brunthal's ice plant is genuinely cold hardy. Rated RHS H4 and USDA 6-11, it lives outdoors all year and needs winter cold rather than protection from it. Its RHS rating of H4 means: Hardy in an average winter across much of the temperate world. On the US scale that maps to USDA 6-11 — 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 −10 to −5 °C. Brunthal's Ice Plant is built for winter — once established it takes hard frost and snow in its stride.

Concretely, for brunthal's ice plant as it gets too cold:

It tolerates winter lows to about −10 to −5 °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 brunthal's ice plant go outside or overwinter — and where?

Plant it out within USDA 6-11 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 brunthal's ice plant can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H4 figure above.

Brunthal's Ice Plant hardiness — frequently asked questions

Is brunthal's ice plant cold hardy?

Yes — brunthal's ice plant is genuinely cold hardy. Rated RHS H4 and USDA 6-11, it lives outdoors all year and needs winter cold rather than protection from it. An outdoor plant. Brunthal's Ice Plant is hardy across USDA 6-11; 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 brunthal's ice plant can survive?

Minimum survivable temperature is roughly about −10 to −5 °C. Brunthal's Ice Plant is built for winter — once established it takes hard frost and snow in its stride.

What hardiness zone is brunthal's ice plant?

Brunthal's Ice Plant is rated USDA 6-11 and RHS H4 — Hardy in an average winter across much of the temperate world.

Can brunthal's ice plant survive winter outside?

Plant it out within USDA 6-11 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 brunthal's ice plant below its minimum temperature?

It tolerates winter lows to about −10 to −5 °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.