UK hardiness
Is Peacock fern hardy in the UK?
Selaginella uncinata
More about peacock fern in the UK
Peacock fern and the RHS hardiness rating
Peacock fern carries an RHS hardiness rating of undefined. Match that rating to the coldest winter your own garden actually sees — UK hardiness is about your local minimum, not a regional map.
This follows the RHS plant hardiness rating system (H1a–H7), the UK standard. For the US growing-zone view, see the peacock fern USDA hardiness guide.
Does UK region change it?
UK winters vary far more by locality than by latitude. Mild western and coastal areas (the south-west, Pembrokeshire, western Scotland's coast) and urban heat islands run several degrees warmer than inland frost pockets, valleys, and exposed eastern sites at the same latitude. A plant marginal on its RHS rating often survives in a sheltered town garden but fails 20 miles inland — so judge by your own coldest recorded night and microclimate (a south-facing wall, a courtyard) rather than the regional average.
Overwintering peacock fern in the UK
For a borderline-hardy plant, the UK winter killers are not just cold air but cold wet roots and wind. Improve drainage before winter, mulch the root zone, move containers to a sheltered spot or against a warm wall, and use horticultural fleece on hard-frost nights. Established plants in free-draining soil take far more cold than a recently planted one in heavy, wet ground.
Peacock fern UK hardiness — frequently asked questions
Is peacock fern hardy in the UK?
Peacock fern is rated RHS undefined. It should be matched to your own coldest winter minimum.
Can peacock fern stay outside over winter in the UK?
In most of the UK, yes, if your garden's coldest night stays within its RHS undefined band. In colder inland or northern gardens, give it a sheltered spot, sharp drainage, and fleece on hard-frost nights.
What does RHS undefined mean?
RHS hardiness ratings run H1a (needs a heated glasshouse) to H7 (survives below -20°C). Match the rating to the lowest temperature your own garden records in winter. The rating is an absolute minimum, not an average.
How do I overwinter peacock fern in the UK?
For a borderline-hardy plant, the UK winter killers are not just cold air but cold wet roots and wind. Improve drainage before winter, mulch the root zone, move containers to a sheltered spot or against a warm wall, and use horticultural fleece on hard-frost nights. Established plants in free-draining soil take far more cold than a recently planted one in heavy, wet ground.
Does UK region change whether peacock fern survives?
UK winters vary far more by locality than by latitude. Mild western and coastal areas (the south-west, Pembrokeshire, western Scotland's coast) and urban heat islands run several degrees warmer than inland frost pockets, valleys, and exposed eastern sites at the same latitude. A plant marginal on its RHS rating often survives in a sheltered town garden but fails 20 miles inland — so judge by your own coldest recorded night and microclimate (a south-facing wall, a courtyard) rather than the regional average.
More peacock fern care
See the full peacock fern care guide, its temperature & humidity needs, and the US (USDA) hardiness version of this page.