Cold hardiness & minimum temperature

Is Chinese Artichoke (Stachys affinis)cold hardy? Hardiness zone & min temp

Also called Chinese artichoke, crosne, Japanese artichoke, artichoke betony.

More about chinese artichoke

About Chinese Artichoke

Stachys affinis · also called Chinese artichoke, crosne · edible

Chinese artichoke (Stachys affinis), also called crosne, is a hardy perennial in the mint family grown for small, knobbly, pearl-white tubers with a crisp, nutty, water-chestnut-like flavour. The plants form spreading clumps of mint-like foliage above networks of edible rhizomes. Tubers are lifted in autumn and winter, eaten raw, pickled or lightly cooked, and the plant can become invasive from missed tubers.

Cold limit: USDA 5-9 · RHS H5 (10-25°C)

What chinese artichoke's hardiness rating actually means

Yes — chinese artichoke is genuinely cold hardy. Rated RHS H5 and USDA 5-9, 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 5-9 — 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. Chinese Artichoke is built for winter — once established it takes hard frost and snow in its stride.

Concretely, for chinese artichoke 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 chinese artichoke go outside or overwinter — and where?

Plant it out within USDA 5-9 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 chinese artichoke can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H5 figure above.

Chinese Artichoke hardiness — frequently asked questions

Is chinese artichoke cold hardy?

Yes — chinese artichoke is genuinely cold hardy. Rated RHS H5 and USDA 5-9, it lives outdoors all year and needs winter cold rather than protection from it. An outdoor plant. Chinese Artichoke is hardy across USDA 5-9; 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 chinese artichoke can survive?

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

What hardiness zone is chinese artichoke?

Chinese Artichoke is rated USDA 5-9 and RHS H5 — Hardy in most of the UK and in cold winters.

Can chinese artichoke survive winter outside?

Plant it out within USDA 5-9 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 chinese artichoke 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.