Echinops ritro subsp. ruthenicus 'Platinum Blue'
This compact selection produces metallic blue heads on silvery white, branching stems. It is valued for the contrast between blue flowers and pale stems. It suits smaller borders and thrives in full sun and well‑drained soils. Bloom is in late summer across much of North America. Plants are useful for cutting and for dried work.
At‑a‑glance
- Group/Class: Herbaceous perennial
- Height × spread: 30–36 in (80–90 cm) × 12–20 in (30–50 cm)
- Bloom window: late summer
- Color & flower form: metallic blue spherical heads; pale stems
- Fragrance: 1 trace
- USDA hardiness: zones 3–8
- Breeder / Year / Origin: unknown
- Cut‑flower notes: Firm stems; good fresh and dried.
- Pet safety: safe
How it differs
- More compact than many blue globe thistles
- Silvery, branched stems add strong contrast
- Reported to come true from seed
- Fits small spaces and containers with excellent drainage
Strengths
- Compact habit
- Tolerates poor, dry soils after establishment
- Pollinator friendly
- Useful fresh or dried
Care in one minute
- Provide full sun and well‑drained soil; amend heavy clay.
- Water regularly in year one; reduce after establishment.
- Avoid over‑fertilizing to keep stems sturdy.
- Deadhead to limit self‑seeding or leave heads for winter display.
Watch‑outs
- Taprooted; avoid moving mature plants
- Can lean in overly rich soil
- Spiny foliage requires gloves for handling
Best uses (tags)
borders; cutting; pollinators; gravel gardens; containers
Provenance note
A compact selection within Echinops ritro subsp. ruthenicus; detailed breeder data are not documented on public profiles.
References
- Royal Horticultural Society – Echinops ritro subsp. ruthenicus ‘Platinum Blue’
- Missouri Botanical Garden – Echinops ritro subsp. ruthenicus
- ASPCA – Echinops spp. non‑toxic to pets
Written by: Your Flowers Guide editorial team
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