Cold hardiness & minimum temperature

Is Jerusalem Artichoke (Helianthus tuberosus 'Fuseau')cold hardy? Hardiness zone & min temp

Also called Fuseau Jerusalem artichoke, sunchoke, earth apple.

More about jerusalem artichoke

About Jerusalem Artichoke

Helianthus tuberosus 'Fuseau' · also called Fuseau Jerusalem artichoke, sunchoke · edible

The Jerusalem artichoke is a tall, sunflower-relative perennial grown for its knobbly underground tubers, not its flowers. 'Fuseau' is prized for its long, smooth, easy-to-peel tubers. Vigorous and almost unkillable, it tolerates poor soil and partial shade, spreads readily from any tuber left in the ground, and is harvested through autumn and winter.

Cold limit: USDA 3-9 (tubers are very cold-hardy and overwinter in the ground) · RHS H6 (18-26°C)

Watch for — Slug and rodent damage to tubers: Slugs, voles and mice nibble tubers left in the ground over winter. Lift as needed and store the rest in damp sand if rodents are a problem.

What jerusalem artichoke's hardiness rating actually means

Yes — jerusalem artichoke is genuinely cold hardy. Rated RHS H6 and USDA 3-9 (tubers are very cold-hardy and overwinter in the ground), it lives outdoors all year and needs winter cold rather than protection from it. Its RHS rating of H6 means: Hardy throughout the UK and northern Europe. On the US scale that maps to USDA 3-9 (tubers are very cold-hardy and overwinter in the ground) — 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 −20 to −15 °C. Jerusalem Artichoke is built for winter — once established it takes hard frost and snow in its stride.

Concretely, for jerusalem artichoke as it gets too cold:

It tolerates winter lows to about −20 to −15 °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 jerusalem artichoke go outside or overwinter — and where?

Plant it out within USDA 3-9 (tubers are very cold-hardy and overwinter in the ground) 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 jerusalem artichoke can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H6 figure above.

Jerusalem Artichoke hardiness — frequently asked questions

Is jerusalem artichoke cold hardy?

Yes — jerusalem artichoke is genuinely cold hardy. Rated RHS H6 and USDA 3-9 (tubers are very cold-hardy and overwinter in the ground), it lives outdoors all year and needs winter cold rather than protection from it. An outdoor plant. Jerusalem Artichoke is hardy across USDA 3-9 (tubers are very cold-hardy and overwinter in the ground); 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 jerusalem artichoke can survive?

Minimum survivable temperature is roughly about −20 to −15 °C. Jerusalem Artichoke is built for winter — once established it takes hard frost and snow in its stride.

What hardiness zone is jerusalem artichoke?

Jerusalem Artichoke is rated USDA 3-9 (tubers are very cold-hardy and overwinter in the ground) and RHS H6 — Hardy throughout the UK and northern Europe.

Can jerusalem artichoke survive winter outside?

Plant it out within USDA 3-9 (tubers are very cold-hardy and overwinter in the ground) 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 jerusalem artichoke below its minimum temperature?

It tolerates winter lows to about −20 to −15 °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.