Key facts
- Gaelic name: Tiodhlac na mara (click to hear the Gaelic pronunciation)
- When to see: May – August
- Species on the Edge areas: North Coast; Shetland; Orkney
- Conservation Status: Red List – Near Threatened
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. The Gaelic name – Tiodhlac na mara – translates literally in English to ‘gift of the sea’.
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 distribution – NBN Atlas https://species.nbnatlas.org/species/NBNSYS0000004018
Habitat
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
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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
Our work for oysterplant
What you can do for oysterplant
Sites where oysterplant grows vary from year to year as storms shift beach materials. Populations are most likely to persist in sheltered sites, whilst plants on more exposed sites can be short-lived. Climate change is likely to increase the frequency of storms and affect oysterplant distribution.
Regular recording each year is vital so we can monitor how Scotland’s oysterplants are doing. Here’s how you can help:
- Familiarise yourself with what an oysterplant looks like.
- Keep your eyes peeled and make a note of when and where you see oysterplants.
- Send in your records here: sote@nature.scot.
- If you can, please try to visit sites each year to check for presence of oysterplants.