Cold hardiness & minimum temperature

Is Ghost Fern (Athyrium 'Ghost')cold hardy? Hardiness zone & min temp

Also called Ghost painted fern.

More about ghost fern

About Ghost Fern

Athyrium 'Ghost' · also called Ghost painted fern · houseplant

Ghost fern is a hybrid of Japanese painted fern and lady fern, prized for its luminous silvery-white, upright fronds that seem to glow in shade. Taller and more upright than a typical painted fern, it is a hardy deciduous woodland plant for cool part-shade and moist, humus-rich soil. Indoors it wants bright shade, steady moisture and a winter rest.

Cold limit: USDA 4-9 (fully hardy garden fern) · RHS H7 (13-22°C)

What ghost fern's hardiness rating actually means

Yes — ghost fern is genuinely cold hardy. Rated RHS H7 and USDA 4-9 (fully hardy garden fern), 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 4-9 (fully hardy garden fern) — 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. Ghost Fern is built for winter — once established it takes hard frost and snow in its stride.

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

Plant it out within USDA 4-9 (fully hardy garden fern) 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 ghost fern can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H7 figure above.

Ghost Fern hardiness — frequently asked questions

Is ghost fern cold hardy?

Yes — ghost fern is genuinely cold hardy. Rated RHS H7 and USDA 4-9 (fully hardy garden fern), it lives outdoors all year and needs winter cold rather than protection from it. An outdoor plant. Ghost Fern is hardy across USDA 4-9 (fully hardy garden fern); 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 ghost fern can survive?

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

What hardiness zone is ghost fern?

Ghost Fern is rated USDA 4-9 (fully hardy garden fern) and RHS H7 — Hardy in the severest European continental winters.

Can ghost fern survive winter outside?

Plant it out within USDA 4-9 (fully hardy garden fern) 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 ghost 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.