perennial

Mediterranean Sea Holly

Eryngium bournonvillei

The Story

Plant Bio

Eryngium bournonvillei, commonly known for its vibrant blue flowers and spiky leaves, is a drought-tolerant perennial that thrives in well-drained soils.

This species is distinctive for its unusual floral structure and is often used in designs for Mediterranean-style gardens.

Uses & Benefits:

Eryngium bournonvillei adds striking blue color and texture to drought-tolerant gardens, thriving in poor soils and full sun.

Its drought tolerance reduces water needs, making it ideal for sustainable landscaping.

Provides nectar for pollinators like bees and butterflies, supporting local ecosystems.

Essentials

At a Glance

Plant Type

Perennial

Height

24 inches

Width

18 inches

Light

Full Sun

Zones

5, 6, 7, 8

Water

Low

Humidity

Low to moderate

Lifespan

Perennial

Native To

Mediterranean

Toxicity

Non-toxic

Bloom period

Mid-summer – Late summer

In flower about 2 months of the year

Planting

How to Grow

Select a well-draining sandy or gravelly soil for planting.
Tuck seeds just below the soil surface and water gently.
Place in full sun for optimal growth and flowering.
Maintain consistent moisture, especially during germination.
Thin seedlings to prevent overcrowding and promote airflow.
Apply a low-nitrogen fertilizer in early spring to encourage blooms.

Pro Tip

Use sharp, clean tools to avoid disease transfer and ensure healthy root development.

Keep It Thriving

Care Guide

Do

Water sparingly to prevent root rot 💧
Deadhead spent flowers to promote continuous blooming
Provide full sun for best growth 🌞
Mulch to conserve moisture and suppress weeds
Fertilize lightly in spring with a balanced fertilizer

Don't

Overwatering can lead to fungal diseases ❌
Avoid heavy clay soils that retain too much water
Don’t disturb roots during flowering
Refrain from excessive fertilization, which can reduce hardiness

Seasonal Care Calendar

Task	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Harvest
Spring Cleanup

Watch Out For

Pests & Diseases

Common Pests

Common Diseases

In the Garden

Landscape Uses & Companions

Landscape Uses

Silver-foliaged borderTextured xeriscape featureOrnamental drought-tolerant garden

Companion Plants

Lavender Salvia Sedum Artemisia Echinacea

Multiply

Propagation Methods

Good to Know

Common Questions

Mediterranean Sea Holly questions

What zones can Mediterranean Sea Holly grow in?

Mediterranean Sea Holly is hardy in USDA Zones 5–8. Inside that range it survives winter in the ground; outside it, grow it as an annual or a container plant you protect.

Is Mediterranean Sea Holly deer resistant?

Yes — Mediterranean Sea Holly is rated deer-resistant. Deer typically pass it over, though extreme hunger can override any plant's defenses.

When does Mediterranean Sea Holly bloom?

Mediterranean Sea Holly typically blooms in mid-summer through late summer. Exact timing shifts a week or two with your zone — Sow's bloom calendar maps it to your garden.

Does Mediterranean Sea Holly need full sun?

Mediterranean Sea Holly does best in full sun (6+ hours).

Is Mediterranean Sea Holly drought tolerant?

Yes — once established (usually after the first full season), Mediterranean Sea Holly handles dry spells with minimal watering. Water deeply its first year to build the root system that makes that possible.