Scientific Name: Blechnum fluviatile

Common Name: ray waterfern

Family Classification (Clade): Pteridophytes

Family: Blechnaceae

Form Description: Small fern forming a low rosette, 20-75cm; fronds prostrate or spreading, pale green thin-textured.

Height (m): 0.2 – 0.75

Municipality
Break O’DayBurnieCentral CoastCentral HighlandsCircular HeadDerwent ValleyDorsetGeorge TownGlamorgan-Spring BayGlenorchyHobartHuon ValleyKentishKingboroughLauncestonMeander ValleyNorthern MidlandsSouthern MidlandsTasmanWaratah-WynyardWest CoastWest Tamar
Plant Communities
RainforestRiparianWet Eucalypt Forest
Habitat Notes

Common and widespread in rainforest, wet sclerophyll and fern gullies, from sea level to exposed sub-alpine creeks. Rare as a lithophyte of waterfalls and wet rock-faces, more common as a terrestrial species of creek and river banks or amongst boulders in riverbeds. Intolerant of dryness.

Site Tolerance

Exposed, Moist, Rocky, Shady, Waterlogged

Soil Tolerance

Fertile, Loam, Poorly-drained, Well-drained

General Notes

Fast growing when in a suitable position. Frog habitat.

Propagation Calendar

  • Flowering Month
    Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
  • Seed Collecting Month
    Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
  • Sowing Month
    Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
  • Cutting Month
    Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Propagation Method
Specialist Method

Seed Information

Seed Collection

Collect spores when mature on the frond. Unripe sori are generally light green then change to yellowish-brown and to dark brown or black when mature. Place fronds, or portions of fronds, containing ripe spores in a paper bag and leave in a dry and draught-free place. Spores should begin to release immediately and all spores are released within days unless the species has tough, leathery fronds. Some species produce large quantities of spores from one frond, others require many fronds to produce similar quantities.

Seed Treatment Method

Standard Scatter seed thinly on to damp potting mix. Hold seed in place by covering with more potting mix to approximately the depth of the seed size.

Seed Treatment Notes

Use a moisture-retaining medium and a pot that allows drainage. Sterilise medium and container with boiling water. Sow spores by sprinkling a small amount onto the surface of the medium. Cover immediately with clean glass or plastic wrap. Leave in a warm area in strong, but not direct, sunlight. Specks of green appear after 2-4 weeks. These are the young prothalli. During the next 6-12 months they are at risk from overcrowding and pathogens. When the first fronds appear the sporelings can be slowly hardened by gradual removal of the container cover. Take care to avoid drying out. Prick out sporelings when the second frond appears.

Germination Time

2-4 weeks

Cutting & Division Information

Ferns producing stolons such as Blechnum species can be propagated by removing offsets from the rootstock. This method has a high success rate.