- Full Sun (At Least 6 Hours Of Direct Sunlight)
- Mature Height 24 - 30 Inches
- Mature Spread 24 - 30 Inches
- Growing Zones 5 - 8
Big Blue Sea Holly, Star Thistle, Blue Sea Holly, or Eryngium x zabelii ‘Big Blue’, is a stunning, low-maintenance perennial, known for its vivid, color-changing foliage. This remarkable Sea Holly produces spiny, basal clumps of silvery-green foliage that unfurls in late spring with thick thistle-like buds. In late summer to early fall, the buds, spiky foliage, and stiff stems take on a purple to bluish tint that deepens and spreads in color as the season progresses, eventually lending these unique plants their vivid color and brushed metallic sheen. Big Blue Sea Holly ranges in height from 24 to 30 inches with an equal spread.
Native to southeastern and central Asia, Big Blue Sea Holly has a stiff, upright growing habit and is relatively drought and salt tolerant, especially once the plant is established, and makes a great coastal option. It is a low-maintenance, easy-to-grow option that is deer and rabbit resistant and attracts both butterflies and critical pollinators. It’s used by florists and gardeners alike to provide a unique and colorful flair to arrangements and bouquets, and makes an excellent dried flower option.
Big Blue Sea Holly Care
Big Blue Sea Holly should be grown in full sun and is very tolerant of hot and dry climates and locations. It can be planted in soil that is dry, sandy and well-drained, slightly acidic to slightly alkaline, and has a pH of 6.0 to 7.8. Sea Holly has deep taproots, which make them difficult to move, so make certain you choose an ideal location before planting. The good news is that this means your Big Blue Sea Holly is drought tolerant. Make certain your Sea Holly has adequate soil drainage. Sea Holly will bloom for a longer period if you deadhead the spent blooms. In late fall or early spring, prune the plants at ground level.
Big Blue Sea Holly Spacing
Big Blue Sea Holly is an excellent option to bring structure and interest to the back of any garden. It should be spaced 2 to 3 inches apart at planting. They look excellent planted alongside coneflower, which can lend them support when they grow tall.
Big Blue Sea Holly Information
USDA Hardiness Zones: 5 - 8 |
Plant Type: Perennials |
Light Exposure: Full Sun (At Least 6 Hours Of Direct Sunlight) |
Mature Height: 24 - 30 Inches |
Mature Spread: 24 - 30 Inches |
Spacing: 24 - 30 Inches |
Habit: Upright |
Flower Color(s): Blue |
Flower Description: |
Bloom Period: July |
Foliage Type: Herbaceous |
Foliage Color(s): Blue, Green, Silver |
Foliage Description: Silvery-Blue. Green |
Seasonal Interest: Summer Flowering |
Watering: Average |
Resists: Deer |
Tolerates: Drought |
Attracts: Bees, Butterflies |
Container Role: |
Uses: Containers, Wildlife Gardens |
Features: Attracts Pollinators, Cut Flowers, Low Maintenance |
Brand: |
Common Name: Big Blue Sea Holly |
Other Name(s): |
Scientific Name: ERYNGIUM `BIG BLUE` |
- SKU:
- 1011894-pc
Container Sizes
Please Note: The pictures below are to give a general representation of the different container sizes. The actual size/ages of plants are estimates and will vary based on; type of plant, time of year, last pruning & many other factors.
For more detailed information, please click here.
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Planter Shipping
Standard Colors: 2-3 business days
Special Order Colors: 8 weeks - this is due to the planter being custom made with the color(s) of your choice
Please Note: On special orders there can not be any cancellations
Plant Shipping
Time of Order:
Summer Shipping
- If there is extreme heat we’ll delay shipping.
- We’ll have to review what areas the plants are traveling through along with your location
Once your plant is shipped you’ll receive an email with tracking information. Depending on the above criteria we’ll ship your plant(s) towards beginning of the following week from your order. We put together this helpful guide of what to do when you receive your plants in the mail.
It is important to know that all of our plants are clearly labeled for which growing zones the plant can survive in. The plants are thoroughly trialed and tested in every growing zone before we state the plant can grow in a zone. Again, our #1 priority is to ship the plants to you healthy and ready to thrive in your location. So we will do everything in our power to do so.