Skip to main content

Oysterplant

Mertensia maritima

Oysterplant
Oysterplant (c) Helen Cromarty

Key facts

  • Gaelic name: Tiodhlac na mara (translation: gift of the sea)
  • Distribution: Orkney, Shetland, Fair Isle, Caithness and Sutherland
  • When to sea: May – August
  • Species on the Edge areas: North Coast; Shetland; Orkney

Species information

 

How to identify

Oysterplant grows close to the ground forming a mat of stems and leaves that is often roughly cirular. It has branching green or purple stems and blue-grey leaves that look quite thick and succulent. The stunning flowers are pink in bud and change to a lovely blue as they open. Flowers develop at the ends of the growing stems often around the edge of the plant. A strong taproot holds the plant securely in place and reaches deep down through the stones or sand to reach nutrients and freshwater.


Lifecycle

Plants start to appear in the stones or sand in May, and flower between June and August. They are at their most obvious in July, when large plants can be over 1.5m in diameter. In winter the leaves and stems die back, and the root system survives underground.


Distribution 

Oysterplant can be found on the North Coast of Scotland, Fair Isle, Shetland and Orkney.


Habitat 

The plant grows on gravelly and sandy seashores, at the top of the beach, usually just within reach of the highest winter tides. It is often the land plant that grows nearest to the sea. Plants that may grow nearby include sea sandwort and lyme grass.
 
On more exposed beaches, like some places in Caithness, it is most likely to be found where the beach is protected by offshore reefs and rocks. Oysterplant likes to grow near streams on the beach (occasionally plants have been found further up firths and river estuaries).

 


Threats

  • Sheep grazing
  • Human damage by trampling, vehicles and gravel collection
  • Climate change (however has both positive and negative impacts for oysterplant) – Oysterplant is adapted to cooler climates. Prolonged periods of hot weather are likely to be damaging for plants in summer, and warmer winters could affect seeds which need winter cold to promote germination. However, increasing frequency and severity of storm events may spread seeds more widely, resulting in new, wider spread populations.

What Species on the Edge is doing

 
 
  • Increased monitoring and surveying to locate strongholds, find new populations and better understand distribution and abundance
  • Training and supporting volunteers to survey oysterplant
  • Growing and planting oysterplants

Gallery

Oysterplant on sand - a plant with blue and purple flowers
Oysterplant (c) Rachael Cooper-Bohannon
A group of people sit on a pebbly beach planting oysterplant
Planting Oysterplant - Urafirth (c) Nathalie Pion
Oysterplant, Stenness, Shetland
Oysterplant, Stenness, Shetland (c) RSPB Scotland
A bed of oysterplant on a beach
Oysterplant (c) Helen Cromarty
Oysterplant
Oysterplant (c) Helen Cromarty
×

Join Our Mailing List!

Stay updated on the latest news and initiatives. Sign up for our mailing list.