How do you recognise Sea holly (Eryngium maritimum)?

Leaf

Liliane Roubaudi, Tela Botanica · CC BY-SA 2.0

Sea holly

Eryngium maritimum L.

Also known as: Sea eryngo

Family: Apiaceae

20 to 50 cm tall

Coastal dunes, dry seaside gardens, sandy soils

Flowering: June – September

Full sun

Hardy to -15°C

❓ How do you recognise this plant?

Its metallic blue colour and its resistance to salt and wind make it an emblematic plant of coastal dunes, now protected. Sea holly has thick, fleshy, blue-grey foliage, adapted to coastal dunes, whereas field eryngo has finer, green, rigid leaves, typical of dry inland wasteland.

🍃 Leaves

Thick, spiny, metallic blue-grey

🌸 Flowers

Small blue-grey umbels surrounded by prickly bluish bracts

🍎 Fruits

Small scaly achenes

🪵 Bark

Rigid blue-grey clump, very deep taproot

🗺️ Distribution

Coasts of Europe (Atlantic, English Channel, Mediterranean); rare and protected on beaches and dunes in France.

🐝 Value for pollinators

Silvery-blue flower heads rich in nectar, attractive to bees and various coastal insects in summer.

✂️ Horticultural uses

Seaside gardens, dry gravel beds; very ornamental bluish foliage, a protected species not to be picked in the wild.

⚠️ Possible toxicity

No known toxicity; spiny foliage that can injure when touched.

⚠️ Look-alike species

Sea holly

Eryngium maritimum

Field eryngo

Eryngium campestre

Sea holly has thick, fleshy, blue-grey foliage, adapted to coastal dunes, whereas field eryngo has finer, green, rigid leaves, typical of dry inland wasteland.

🌿 Other Apiaceae to discover

ℹ️ Educational profile — do not use it to judge whether a plant is edible or safe.

🌱 This database is constantly evolving — species and information are added and corrected regularly. Spotted a mistake? Report it below.