Blechnum nudum

Blechnum nudum

Fishbone water fern

  • Botanical name: Blechnum nudum
  • Common name: Fishbone water fern
  • Family: Blechnaceae
  • Plant Type: Perennial, Evergreen
Foliage colour:


Fishbone water fern, Blechnum nudum, is a great fern for a bog garden, forming an erect, rounded clump with a small black fibrous trunk. Shuttlecocks of dark green, glossy pinnate fronds appear throughout summer. Slender, spore-bearing fronds grow from the centre.


Grow Blechnum nudum in boggy soil in partial shade. Protect from frost. 

How to grow Blechnum nudum

  • Plant size

    100cm height

    100cm spread

  • Aspect

    North facing, east facing, south facing, west facing

  • Sun exposure: Partial shade
  • Soil type: Boggy

Plant calendar

A table displaying which months are best to sow, plant and harvest.
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Do not Plant in January

Do not Plant in February

Do not Plant in March

Do not Plant in April

Do Plant in May

Do Plant in June

Do not Plant in July

Do not Plant in August

Do not Plant in September

Do not Plant in October

Do not Plant in November

Do not Plant in December

Blechnum nudum and wildlife

Blechnum nudum has no particular known value to wildlife in the UK.

Is Blechnum nudum poisonous?

Blechnum nudum has no toxic effects reported.

No reported toxicity to:

No reported toxicity to Birds

No reported toxicity to Cats

No reported toxicity to Dogs

No reported toxicity to Horses

No reported toxicity to Livestock

No reported toxicity to People