Mediterranean sea holly
Eryngium bourgatii ·
Crisp, deeply cut, dark green leaves veined in white, a pattern as good as any flower, below blue-grey thistle heads on blue stems.
- Size
- 18 in tall, 18 in wide
- Zones
- 5 to 9
- Light
- Full sun
- Flowers
- Late June to early August
- Pets
- Not checked
- Job in a bed
- Accent
A bed built around mediterranean sea holly
The planner designed this bed around mediterranean sea holly when this page was made: a 12 × 6 ft (3.7 × 1.8 m) English border in zone 6, full sun. It chose the other plants from the 715 that suit those conditions and its dry soil, and says below why mediterranean sea holly stands where it does.
The plants
- 1 Mediterranean sea holly × 3, blue
- 2 Yellow ice plant × 8, yellow
- 3 October daphne × 5, pink
- 4 Little bluestem 'The Blues' × 5, tan
- 5 Stiff goldenrod × 5, yellow
- 6 Dwarf English boxwood × 1, dark green leaves
- 7 Spring starflower × 12, white
- 8 Star of Persia × 4, purple
Why this plant
- The only blue.
Why here
- In the middle. At 18 in it is the step between October daphne (8 in) in front and little bluestem 'The Blues' (3 ft) behind: each is seen over the one before.
- 3 plants in 3 places. An accent is a punctuation mark: the repeat along the bed gives it rhythm.
Why now
- In flower for 7 weeks. From late June to early August.
- Fills a gap. For six of those weeks nothing else on the plan is in flower.
Planned as an English border: 4 of the 4 groups (100%) are drifts, longer along the bed than they are deep. When the flowers are over, three kinds, among them yellow ice plant and little bluestem 'The Blues', keep the bed from looking bare. The back corners are held by little bluestem 'The Blues' and stiff goldenrod, the tallest plants on the plan.
The planner's own design check: 14 Excellent, 2 Good, 1 Satisfactory. It flags one thing to watch: Nothing on this plan is highly poisonous or an aggressive spreader.
Open this bed in the planner Change its size, the sun or the style, move plants about, or swap one for another.
Where mediterranean sea holly goes in a border
At 18 in it belongs at the front of a bed. In the planner's ten height classes it is short (12 to 18 in).
Its job: accent. An upright plant used singly, like a punctuation mark, and repeated at intervals to give the bed rhythm.
The sea holly to grow for foliage. Low enough for the front of a gravel bed, where the marbled rosettes can be seen. Taprooted, so plant it young and leave it alone.
- Patterned foliage for gravel gardens
- The front of a dry border
- Dried flowers
What to plant with mediterranean sea holly
Plants recorded as good partners for it, and what each pairing does:
- Blue fescue: its blue-green leaves are a setting for the flowers, before and after; low enough (10 in) to stand in front of it; happy in the same dry soil.
- Sedum 'Angelina': its chartreuse leaves are a setting for the flowers, before and after; low enough (5 in) to stand in front of it; happy in the same dry soil.
- English lavender 'Hidcote': in flower together for six weeks, from late June; spires rising out of its mound; happy in the same dry soil.
Questions about mediterranean sea holly
Does mediterranean sea holly need sun or shade?
Mediterranean sea holly grows in full sun (6 or more hours of direct sun a day).
It wants dry, sharply drained soil, on the lean side, with no feeding, and little watering once settled.
What zones does mediterranean sea holly grow in?
USDA zones 5 to 9. It is hardy to zone 5, which means it survives winter nights down to about −10 °F (−23 °C).
Gardening in Canada? Use the USDA zone for your town: Canada's own zone map uses different numbers.
When does mediterranean sea holly flower in my zone?
In zone 5 it flowers late June to early August. As a summer flower it moves about half a week for every zone: earlier where it is warmer.
| Zone 5 | Late June to early August |
|---|---|
| Zone 6 | Late June to early August |
| Zone 7 | Mid June to late July |
| Zone 8 | Mid June to late July |
| Zone 9 | Early June to mid July |
Worked out from Hopkins' bioclimatic law: spring arrives about four days later for each degree of latitude north, and one zone is roughly two degrees. A warm spring or a cold one moves any garden two weeks either way.
How far apart should mediterranean sea holly be planted?
16 in (40 cm) apart, from the middle of one plant to the middle of the next. That is a little closer than its full width of 18 in (45 cm), so a group knits into one patch.
It grows 18 in (45 cm) tall. Give it the full distance from anything taller, or it will lean out towards the light.
How many mediterranean sea holly plants do I need?
At 16 in apart, set out in staggered rows:
- 7 to fill 10 square feet (about 1 m²)
- 8 for a single row 10 ft (3 m) long
- 21 to fill a 4 × 8 ft bed on its own
In a mixed border, plant it as one at a time, repeated along the bed at intervals; a slender one reads better as a clump of three.
In the bed above, the planner used three in three groups.
Is there a native plant like mediterranean sea holly?
Mediterranean sea holly is not native to North America. These North American natives come closest to doing its job:
- Stokes' aster: the same size, the same flowering time and the same colour; a drift, not an accent, wants average soil.
- Tickseed 'Early Sunrise': the same size; a drift, not an accent, flowers early June to late August.
- Scarlet coral bells: the same size; an edging, not an accent, flowers late May to late July.
Matched the way the planner's Swap button matches plants: the same job in a bed, then size, then flowering time.
What flowers after mediterranean sea holly?
Mediterranean sea holly is over by early August. These start as it finishes and carry the same spot on, so it never goes flat:
- Lilyturf: from early August to mid September, 16 in tall.
- Sedum 'Autumn Joy': from mid August to mid October, 24 in tall.
- Black-eyed Susan 'Goldsturm': from late July to late September, 2 ft tall.
What does mediterranean sea holly look like in winter?
Mediterranean sea holly dies down to the ground and there is nothing to see until spring. The old stems can be cut in autumn, or left until spring as shelter for overwintering insects.
More Eryngium
- Alpine sea holly Eryngium alpinum
- Miss Willmott's ghost Eryngium giganteum
- Rattlesnake master Eryngium yuccifolium
- Sea holly Eryngium planum
- Sea holly 'Big Blue' Eryngium x zabelii 'Big Blue'
- Sea holly 'Blue Hobbit' Eryngium planum 'Blue Hobbit'
In these guides
Every fact on record
- Type
- Perennial
- Size
- 18 in (45 cm) tall, 18 in (45 cm) wide
- Plant
- 16 in (40 cm) apart
- Height class
- Short (12 to 18 in)
- Place in the bed
- Front
- Flowers
- Late June to early August; globes; blue
- Leaves
- Medium texture, herbaceous; dark green, silver
- Shape
- Mounding, clumping
- Hardy in
- USDA zones 5 to 9
- Light
- Full sun
- Soil
- Lean, dry and sharply drained
- Water
- Low
- Feeding
- None needed
Not yet checked against an outside reference: its figures rest on general horticultural knowledge. Flowering times are for zone 5: later in colder zones, earlier in warmer ones. Toxicity and spread information is a general gardening guide, not veterinary or medical advice, and invasive status varies by region. If a person or pet eats a plant, contact poison control or a vet. Check your local invasive species list before planting anything with a spread warning.