Eryngium Magical Silver

Eryngium ‘Magical Silver’ (Sea Holly) is a stunning, architectural perennial with a cooler, more modern look. It produces eye-catching, spiky flower heads in silvery, metallic tones, often with a frosty sheen that looks incredible in sunlight. The bold, sculptural shape makes it perfect for adding texture and structure to borders, and it pairs beautifully with ornamental grasses and other prairie-style plants.

As well as looking fantastic in the garden, Eryngium is a brilliant cut flower. Stems can be used fresh or dried, holding their shape and colour for long-lasting arrangements. Tough, drought-tolerant and low maintenance once established, it’s a great choice for sunny, well-drained spots.

Planting Instructions

When to Plant:

Plant bare root Eryngium in spring or autumn, while the soil is moist and workable. Avoid planting when the ground is frozen or waterlogged.

Where to Plant:
Choose a sunny position with well-drained soil. Eryngium thrives in poor, gritty or sandy soils and dislikes heavy, wet ground. Ideal for gravel gardens, coastal gardens, prairie-style planting and wildlife-friendly borders. The more sun and drainage it gets, the better the colour.

How to Plant:

• Before planting: Soak the bare roots in water for 30–60 minutes to rehydrate.
• Depth: Plant so the crown sits level with the soil surface.
• Spacing: Space plants 30–45 cm (12–18 inches) apart.
• Soil Prep: Avoid rich compost. Instead, improve drainage with grit on heavier soils and keep the planting area relatively lean.

Watering:
Water well after planting. Keep watered during the first growing season while roots establish. Once established, Eryngium is drought tolerant and only needs watering during prolonged dry spells.

Aftercare Tips:

• Leave flower heads for winter interest and wildlife, then cut back in late winter or early spring.
• Avoid heavy feeding—too much fertility can reduce colour and cause softer growth.
• Eryngium dislikes being moved once established, so choose its spot carefully.

Top Tip:
‘Magical Silver’ looks incredible with purples and blues—try pairing with Salvias, lavender and Achillea for a border that looks like it’s been designed by a pro.

Plant Details

Flowering Period:
July - September

Height:
24–36" (60–90cm) approx.

Position:
Full sun

Hardy Perennial