Eryngium pandanifolium (Giant Sea Holly)

One of the largest of the Eryngiums, Eryngium pandanifolium (Giant Sea Holly) is an evergreen perennial forming a bold rosette of narrowly sword-shaped, spiky-margined, arching, blue-green leaves. From mid-summer to early fall, it produces tall stems bearing towering umbels of small, tight, egg-shaped reddish-purple flower heads.

One of the largest of the Eryngiums, Eryngium pandanifolium (Giant Sea Holly) is an evergreen perennial forming a bold rosette of narrowly sword-shaped, spiky-margined, arching, blue-green leaves. From mid-summer to early fall, it produces tall stems bearing towering umbels of small, tight, egg-shaped reddish-purple flower heads. They may turn chocolate brown if not damaged by frost. Attractive to bees and butterflies but deer resistant, this fast-growing and imposing Sea Holly adds a dramatic architectural presence in the garden.

  • Recipient of the prestigious Award of Garden Merit of the Royal Horticultural Society.
  • Grows in clumps of stiffly erect, branched stems up to 7-8 ft. tall (210-240 cm) and 4-5 ft. wide (120-150 cm)
  • Performs best in full sun in moist, well-drained soils. Best situated in a sheltered site where it has some protection from the prevailing winds.
  • Excellent choice for beds and borders, cottage gardens and coastal gardens. May be planted as a single specimen or in groupings.
  • Cut back old flowering stems after they have finished
  • Watch for leaf and bud eelworms, powdery mildew and root rot.
  • Propagate by seed sown in containers in a cold frame as soon as ripe. Divide clumps in spring, although they may be slow to re-establish, or take root cuttings in late winter
  • Propagate by root cuttings in late winter
  • Native to South America

Requirements

Hardiness 9
– 10

Heat Zones 9
– 12

Plant Type Perennials
Plant Family Eryngium – Sea Hollies
Exposure Full Sun
Season of Interest Summer (Mid,Late)Fall
Height 7'
– 8'
(210cm
– 240cm)
Spread 4'
– 5'
(120cm
– 150cm)
Spacing 60″ (150cm)
Water Needs Average
Maintenance Low
Soil Type Chalk, Loam, Sand
Soil pH Acid, Alkaline, Neutral
Soil Drainage Moist but Well-Drained, Well-Drained
Characteristics Plant of Merit, Showy, Evergreen
Tolerance Deer, Salt
Attracts Bees, Birds, Butterflies
Garden Uses Beds and Borders
Garden Styles City and Courtyard, Coastal Garden, Informal and Cottage