Cold hardiness & minimum temperature

Is Ostrich Fern (Matteuccia struthiopteris)cold hardy? Hardiness zone & min temp

Also called Shuttlecock fern, Fiddlehead fern.

More about ostrich fern

About Ostrich Fern

Matteuccia struthiopteris · also called Shuttlecock fern, Fiddlehead fern · edible

The ostrich fern is a striking deciduous fern forming tall, vase-shaped shuttlecocks of feathery fronds and the source of edible fiddleheads harvested in spring. It loves cool, damp, shaded ground and spreads by runners to colonise moist woodland. Fiddleheads are a prized vegetable but must be cooked thoroughly, as raw or undercooked ones cause illness.

Cold limit: USDA 2-7 (outdoors); needs cool conditions · RHS H7 (5-24°C)

What ostrich fern's hardiness rating actually means

Yes — ostrich fern is genuinely cold hardy. Rated RHS H7 and USDA 2-7 (outdoors); needs cool conditions, 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 2-7 (outdoors); needs cool conditions — 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. Ostrich Fern is built for winter — once established it takes hard frost and snow in its stride.

Concretely, for ostrich fern 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 ostrich fern go outside or overwinter — and where?

Plant it out within USDA 2-7 (outdoors); needs cool conditions 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 ostrich fern can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H7 figure above.

Ostrich Fern hardiness — frequently asked questions

Is ostrich fern cold hardy?

Yes — ostrich fern is genuinely cold hardy. Rated RHS H7 and USDA 2-7 (outdoors); needs cool conditions, it lives outdoors all year and needs winter cold rather than protection from it. An outdoor plant. Ostrich Fern is hardy across USDA 2-7 (outdoors); needs cool conditions; 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 ostrich fern can survive?

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

What hardiness zone is ostrich fern?

Ostrich Fern is rated USDA 2-7 (outdoors); needs cool conditions and RHS H7 — Hardy in the severest European continental winters.

Can ostrich fern survive winter outside?

Plant it out within USDA 2-7 (outdoors); needs cool conditions 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 ostrich fern 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.