Sea Holly Blue Seeds (Eryngium alpinum)

Striking and architectural, Sea Holly Blue produces spiky, thistle-like blooms in a unique metallic blue, surrounded by ruffled bracts. Its dramatic texture and shimmering color add bold contrast to borders and cut flower arrangements. Drought-tolerant and long-lasting, it’s a magnet for bees and butterflies.

What Makes It Special

• Unusual metallic-blue, spiky blooms

• Drought-tolerant and hardy perennial

• Excellent cut flower, fresh or dried

Key Features

• Botanical name: Eryngium alpinum

• Hardy perennial

• Height: 60–90 cm (24–36 in)

• Bloom time: Summer

Ideal For

• Architectural accents in borders

• Cottage, coastal, and wildlife gardens

• Fresh and dried flower arrangements

Sowing

• Sow indoors Feb–Apr or outdoors May–Jun

• Requires stratification: mix seeds with moist compost, refrigerate 2–4 weeks

• Germination: 14–35 days at 18–22°C after cold treatment

• Thin seedlings 40 cm apart

• Flowers from the second year after sowing