Linum perenne 'Sapphire'
Linum perenne ‘Sapphire’ is a compact selection of perennial flax with many sky blue flowers. Plants stay low and neat which fits small borders and containers. Peak bloom comes in late spring in full sun. This cultivar stands out for small stature with a long flush in lean soils. It performs best in full sun with well drained soil and light summer irrigation.
At‑a‑glance
- Group/Class: Cultivar
- Height × spread: 12 to 20 in (30 to 50 cm) × 12 to 20 in (30 to 50 cm)
- Bloom window: late spring to early summer
- Color & flower form: sky blue; five petaled, saucer shaped
- Fragrance: 0 none
- USDA hardiness: zones 4 to 8
- Breeder / Year / Origin: unknown; recorded as ‘Blau Saphir’ in Europe
- Cut‑flower notes: Short stems; use as a light filler. Trials of perennial flax report about 9 days with preservative for L. perenne cuts.
- Pet safety: unknown
How it differs
- Shorter and denser than typical L. perenne.
- Useful in edging and pots where taller forms sprawl.
- Cold hardy for a cultivar and suited to northern gardens.
- Blooms heavily for several weeks in late spring.
Strengths
- Compact habit with steady bloom
- Performs in lean, well drained soils
- Tolerates light afternoon shade in hot sites
- Good choice for small spaces and rock gardens
Care in one minute
- Site: full sun; light shade increases bloom duration in heat
- Soil: well drained, low to average fertility
- Water: low to moderate; avoid constant wetness
- Feeding: none; excess fertility reduces bloom
- Grooming: shear lightly after peak; leave some seed for renewal
Watch‑outs
- Short lived; allow some seedlings to renew clumps
- Petals fall by afternoon; normal for the genus
- Declines in poorly drained or highly fertile soils
Best uses (tags)
edging, rock gardens, containers, cutting, meadows
Provenance note
Listed by the Royal Horticultural Society as ‘Blau Saphir’ and grown in public gardens; exact breeder and year are unknown.
References
- RHS Plants: Linum perenne ‘Blau Saphir’ (‘Blue Sapphire’)
- Chicago Botanic Garden Plant Finder: Blue Sapphire perennial flax
- ASHS HortScience 2022: Perennial Flax as a Cut Flower
Written by: Your Flowers Guide editorial team
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