Eryngium planum Blue Cap (Flat Sea Holly)

Eryngium Planum 'Blue Cap' (Flat Sea Holly) is a clump-forming perennial with a profusion of small, steel-blue flowers, tightly packed into egg-shaped heads, that light up the garden throughout summer. Each flower is adorned with a spiky collar of narrow bracts. They are produced on silver-blue stems and stand high above the basal rosette of blue-tinged, deeply toothed, smooth textured leaves. Its beautiful texture, unique color, long-lasting flowering, easy care, and remarkable qualities as cut flowers make it a favorite of florists, gardeners, bees, and butterflies. Eryngium planum is one of the hardiest sea hollies, and it has proven to be a reliable, long-lived perennial.

• Grows in clumps of stiffly erect, branched stems up to 2-3 ft. tall (60-90 cm) and 18-24 in. wide (45-60 cm).
• Thrives in full sun in dry, sandy, well-drained soils. The sunnier the site, the more intense the blue! Tolerates poor soils. Avoid planting this plant in moist and fertile soils, where it will tend to sprawl and may require support.
• Excellent choice for sun-baked, informal beds and borders or naturalistic plantings, where the steel blue flowers and foliage will superbly complement the vibrantly colored summer flowers. Ideal for small gardens. May be planted as a single specimen or in groupings. Perfect for cut or dried flower arrangements too!
• Deadhead to preserve a neat appearance. Cut back in late summer after flowering is over.
• Self-seeding may happen under satisfactory growing conditions but rarely becomes a nuisance.
• Transplants poorly and is best left undisturbed once established.