About

Cystopteris fragilis, the brittle bladder fern, is a clustering, summer-green fern about 20 cm tall with erect rhizomes and tufts of lance-shaped, pale silvery-green fronds to 45 cm long with sharply pointed segment tips. A delicate and ornamental native fern for a sheltered, shaded, moist rock garden or wall crevice.

About the genus

Cystopteris, the bladder ferns, are rhizomatous, deciduous perennial ferns with delicate, pale-green, deeply divided fronds and rounded, inflated spore cases. Native to cool, shaded, rocky habitats, they are graceful and ornamental ferns for sheltered, shaded garden positions.

Growing conditions

SunlightPartial shade
Soil typeClay, Loam
Soil pHAcid, Alkaline, Neutral
Soil moistureMoist but well-drained
AspectNorth-facing, East-facing
ExposureSheltered
UK hardinessH7

Plant details

Plant typeFerns
HabitTufted
FoliageDeciduous
Height0.1-0.5 metres
Spread0.1-0.5 metres
Time to full height2-5 years
Suggested usesCity and courtyard gardens, Cottage and informal garden, Rock garden

Care notes

CultivationGrow in fertile, moist but well-drained soil in partial shade with shelter from cold, drying winds
PruningTidy spent leaves in autumn
PropagationPropagate by division in spring or plant bulbils in late summer
Pest resistanceGenerally pest-free
Disease resistanceGenerally disease-free