Cold hardiness & minimum temperature

Is Sedum 'Autumn Joy' (Hylotelephium 'Herbstfreude')cold hardy? Hardiness zone & min temp

Also called Autumn Joy sedum, Autumn Joy stonecrop.

More about sedum 'autumn joy'

About Sedum 'Autumn Joy'

Hylotelephium 'Herbstfreude' · also called Autumn Joy sedum, Autumn Joy stonecrop · flowering

An iconic upright border stonecrop grown for fleshy blue-green foliage and broad domed flowerheads that open dusky pink in late summer, deepen to coppery-russet, then dry to bronze seedheads that hold through winter. Drought-tough and a magnet for bees and butterflies, 'Autumn Joy' is one of the most reliable late-season perennials.

Cold limit: USDA 3-9 · RHS H7 (-34 to 32°C)

Watch for — Crown and root rot: Wet winter soil rots the succulent crown; ensure sharp drainage and avoid soggy sites.

What sedum 'autumn joy''s hardiness rating actually means

Yes — sedum 'autumn joy' is genuinely cold hardy. Rated RHS H7 and USDA 3-9, 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 3-9 — 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 below about −20 °C. Sedum 'Autumn Joy' is built for winter — once established it takes hard frost and snow in its stride.

Concretely, for sedum 'autumn joy' 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 sedum 'autumn joy' go outside or overwinter — and where?

Plant it out within USDA 3-9 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 sedum 'autumn joy' can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H7 figure above.

Sedum 'Autumn Joy' hardiness — frequently asked questions

Is sedum 'autumn joy' cold hardy?

Yes — sedum 'autumn joy' is genuinely cold hardy. Rated RHS H7 and USDA 3-9, it lives outdoors all year and needs winter cold rather than protection from it. An outdoor plant. Sedum 'Autumn Joy' is hardy across USDA 3-9; 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 sedum 'autumn joy' can survive?

Minimum survivable temperature is roughly below about −20 °C. Sedum 'Autumn Joy' is built for winter — once established it takes hard frost and snow in its stride.

What hardiness zone is sedum 'autumn joy'?

Sedum 'Autumn Joy' is rated USDA 3-9 and RHS H7 — Hardy in the severest European continental winters.

Can sedum 'autumn joy' survive winter outside?

Plant it out within USDA 3-9 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 sedum 'autumn joy' 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.