Eryngium alpinum | Alpine Sea Holly
Long-lasting, thistle-like flowers with a metallic sheen of blue to purple are produced on stiff, branched, upright stems in summer. Ideal for providing colour and coarse contrast in borders. Flower stems, when cut just after beginning to open, make excellent vase subjects.
Exposure: Full Sun Bloom Time: Summer Height x Width: 20-40" x 4-20" Hardiness: -40°C to -34°C USDA Zone: 3