Sefton Coast Wildlife

Grass of Parnassus

Parnassia palustris

UK Amber ListModerate📍 Ainsdale NNR
Season
Flowers August–October. One of the last dune plants to flower.
Best time of day
Any time in sunshine — flowers close in overcast conditions
Sefton Coast
One of the most important populations in England — hundreds of plants in suitable dune slacks
UK population
Declining in England; strongholds in northern England, Scotland and Ireland

Tap image to enlarge · Wikimedia Commons

Overview

Grass of Parnassus is one of the botanical jewels of the Sefton Coast and one of the reasons Ainsdale NNR has international importance. The white flowers with delicate green veining are beautiful and the plant only grows in very specific conditions — wet, calcareous dune slacks. It's declining nationally and the Sefton dune system is one of its strongholds in England. Look for it in August and September.

At a Glance

OrderCelastrales
FamilyCelastraceae
HabitatDamp calcareous dune slack · Wet grassland · Base-rich marsh
UK populationDeclining in England; strongholds in northern England, Scotland and Ireland
Sefton CoastOne of the most important populations in England — hundreds of plants in suitable dune slacks
ConservationUK Amber List

Where to See It

Dune slacks at Ainsdale NNR. Wet, calcareous ground in the dune system. Ask NNR wardens for current locations.

Identification

Solitary white flower with distinctive translucent petals veined with green. Kidney-shaped leaves at base. Single stem with clasping leaf. To 20cm.

Viewing & Photography Tips

Visit Ainsdale NNR in late August or September. The boardwalk crosses some of the best slack habitat. The flowers stand up well and are hard to miss once you know them. Wardens can advise on best locations.

Conservation Status

UK Amber List

This species is of moderate conservation concern. Population monitoring and habitat management on the Sefton Coast support its continued recovery.

Frequently Asked Questions

Why is Grass of Parnassus significant at Ainsdale NNR?

Ainsdale NNR holds one of the most important populations of Grass of Parnassus in England. The plant is restricted to wet, calcareous dune slacks — a rare and declining habitat. The Sefton Coast dune system is one of the few remaining sites where this habitat is extensive enough to support large populations. Natural England management specifically protects the slack hydrology to maintain this species.

Is Grass of Parnassus actually a grass?

No. Despite its common name, Grass of Parnassus is not a grass at all — it is a small flowering plant in the family Celastraceae, related to spindles and bittersweet. The 'grass' in the name refers to the habitat (grassland on Mount Parnassus in Greece) rather than the plant's appearance. It has kidney-shaped leaves and a single, beautiful white flower.

Related Species

Plan your visit to the Sefton Coast

Marshside RSPB, Formby pinewoods, Ainsdale NNR — practical guides to getting there, what to bring, and the best spots for each season.