Cold hardiness & minimum temperature

Is Scot's Maidenhair Spleenwort (Asplenium viride)cold hardy? Hardiness zone & min temp

Also called Green Spleenwort, Viride Spleenwort.

More about scot's maidenhair spleenwort

About Scot's Maidenhair Spleenwort

Asplenium viride · also called Green Spleenwort, Viride Spleenwort · houseplant

Green spleenwort is a small, hardy alpine fern of cool, limestone rocks and crevices across northern and montane regions. Its tufted fronds have a distinctive bright-green stalk (unlike the black-stemmed maidenhair spleenwort). It is a cool-growing rock fern best suited to a shaded crevice, trough, or alpine pot rather than a warm living room, needing sharp drainage and lime.

Cold limit: USDA 4-7 (cold-hardy alpine; dislikes summer heat) · RHS H6 (2-18°C)

What scot's maidenhair spleenwort's hardiness rating actually means

Yes — scot's maidenhair spleenwort is genuinely cold hardy. Rated RHS H6 and USDA 4-7 (cold-hardy alpine; dislikes summer heat), 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 4-7 (cold-hardy alpine; dislikes summer heat) — 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. Scot's Maidenhair Spleenwort is built for winter — once established it takes hard frost and snow in its stride.

Concretely, for scot's maidenhair spleenwort 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 scot's maidenhair spleenwort go outside or overwinter — and where?

Plant it out within USDA 4-7 (cold-hardy alpine; dislikes summer heat) 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 scot's maidenhair spleenwort can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H6 figure above.

Scot's Maidenhair Spleenwort hardiness — frequently asked questions

Is scot's maidenhair spleenwort cold hardy?

Yes — scot's maidenhair spleenwort is genuinely cold hardy. Rated RHS H6 and USDA 4-7 (cold-hardy alpine; dislikes summer heat), it lives outdoors all year and needs winter cold rather than protection from it. An outdoor plant. Scot's Maidenhair Spleenwort is hardy across USDA 4-7 (cold-hardy alpine; dislikes summer heat); 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 scot's maidenhair spleenwort can survive?

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

What hardiness zone is scot's maidenhair spleenwort?

Scot's Maidenhair Spleenwort is rated USDA 4-7 (cold-hardy alpine; dislikes summer heat) and RHS H6 — Hardy throughout the UK and northern Europe.

Can scot's maidenhair spleenwort survive winter outside?

Plant it out within USDA 4-7 (cold-hardy alpine; dislikes summer heat) 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 scot's maidenhair spleenwort 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.