Sea Holly
Eryngium elevatum
Essentials
At a Glance
Plant Type
Perennial
Height
30 inches
Width
18 inches
Light
Full Sun
Zones
4, 5, 6, 7, 8, 9
Water
Low
Humidity
Low to moderate
Lifespan
Perennial
Native To
Mexico
Toxicity
Spiny bracts can cause skin irritation.
The Story
Plant Bio
Eryngium elevatum, a species of Sea Holly, is an upright, clump-forming perennial prized for its architectural form. It features thistle-like, blue to amethyst flower heads on branching stems, surrounded by spiny bracts, which attract a wide range of pollinators. Native to Mexico, this species stands out with its tall, branching stems bearing numerous small, ovoid flower heads. The entire plant, from stems to bracts, often takes on a striking metallic blue or amethyst hue.
Bloom Period:
Uses & Benefits:
Marketplace
Where to Buy
Shipping costs Year-round shipping Free shipping
Planting
How to Grow
- Choose well-drained sandy or gravelly soil for planting.
- Tuck seeds into the soil surface and water gently after sowing.
- Allow seedlings to establish for 4-6 weeks before thinning.
- Transplant mature plants in early spring or fall for best results.
- Mist cuttings in a humid environment to promote root growth.
- Apply a light mulch to conserve moisture and suppress weeds.
Pro Tip
Ensure excellent drainage to prevent root rot and promote healthy growth.
Keep It Thriving
Care Guide
Do
- Water sparingly, allowing soil to dry out between watering 🌱
- Prune dead or damaged stems to maintain shape
- Apply a balanced, low-nitrogen fertilizer in early spring
Don't
- Avoid overwatering, which can cause root rot ❌
- Don’t disturb roots excessively during pruning
- Refrain from using heavy, clay-rich soils
Seasonal Care Calendar
| Task | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Divide | ||||||||||||
| Harvest | ||||||||||||
| Mulch | ||||||||||||
| Plant | ||||||||||||
| Spring Cleanup |
Watch Out For
Pests & Diseases
Common Pests
Common Diseases
In the Garden
Landscape Uses & Companions
Landscape Uses
Companion Plants
Multiply
Propagation Methods
Good to Know
Common Questions
Sea Holly questions
What zones can Sea Holly grow in?
Sea Holly is hardy in USDA Zones 4–9. Inside that range it survives winter in the ground; outside it, grow it as an annual or a container plant you protect.
Is Sea Holly deer resistant?
Yes — Sea Holly is rated deer-resistant. Deer typically pass it over, though extreme hunger can override any plant's defenses.
When does Sea Holly bloom?
Sea Holly typically blooms in late summer through early fall. Exact timing shifts a week or two with your zone — Sow's bloom calendar maps it to your garden.
Does Sea Holly need full sun?
Sea Holly does best in full sun (6+ hours).
Is Sea Holly drought tolerant?
Yes — once established (usually after the first full season), Sea Holly handles dry spells with minimal watering. Water deeply its first year to build the root system that makes that possible.
More Eryngium to compare
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Eryngium yuccifolium
Big Blue Sea Holly
Eryngium x hybrida 'Big Blue'
Blue Glitter Sea Holly
Eryngium planum 'Blue Glitter'
Blue Hobbit Eryngium
Eryngium x zabelii 'Blue Hobbit'
Picos Blue Sea Holly
Eryngium bourgatii 'Picos Blue'
Jos Eijking Sea Holly
Eryngium x hybrida 'Jos Eijking'
Keep exploring
Explore the genus
Collections featuring this plant
Grow Sea Holly with confidence
See it in a design of your actual yard, get zone-matched care reminders, and track it season by season in your garden journal.
