Eryngium ‘Big Blue’, commonly referred to as Rattlesnake Master, is a striking non-native hybrid perennial known for its spiny, metallic-blue flower heads and deeply toothed silver-blue foliage. Blooming from mid to late summer, this clump-forming plant grows 24 to 36 inches tall and thrives in sunny, well-drained locations. Its sculptural form and drought tolerance make it an eye-catching addition to dry gardens, pollinator beds, and xeriscapes. While ornamental and pollinator-friendly, ‘Big Blue’ is not native and provides less ecological benefit than true North American species.

Why choose ‘Big Blue’ Rattlesnake Master:

• Unique form: Metallic-blue thistle-like blooms add bold texture and color

• Long bloom time: Flowers last from midsummer into early fall

• Drought tolerant: Ideal for dry, sunny, low-maintenance garden spaces

Cultivating tips:

• Sun exposure: Requires full sun for strong flowering and upright growth

• Soil needs: Well-drained soil; tolerates poor or sandy conditions

• Maintenance: Minimal—deadhead if desired or leave seed heads for winter interest

Designs for your garden:

• Xeriscapes: Perfect for water-wise landscapes and dry borders

• Pollinator gardens: Attracts bees, butterflies, and beneficial insects

• Contrast plantings: Pairs well with native grasses and soft-textured perennials

Ecological considerations:

• Non-native hybrid: Offers some pollinator support but limited wildlife value

• Best paired with natives: Combine with native species to build biodiversity

• Ornamental use: Great for cut flowers and winter interest in structured beds

Looking for native alternatives?

Eryngium yuccifolium – Rattlesnake Master: A true native with spiky, globe-shaped white flowers and sword-like foliage, ideal for prairie and pollinator gardens.
Liatris spicata – Blazing Star: A tall, spiky native perennial with vivid purple flowers that attract butterflies and thrive in sunny, well-drained soil.
Echinacea purpurea – Purple Coneflower: A reliable native with bold purple blooms, excellent for pollinators and birds in dry or prairie-style plantings.