Linum lewisii
Linum lewisii is the North American blue flax native to open, well drained sites from Alaska to the Southwest. It is grown for sky blue flowers that open in the morning and drop by midday. Plants are short lived but they self sow in lean soils. This species stands out for cold and drought tolerance in sunny sites. It performs best in full sun with fast drainage in the western and northern United States.
At‑a‑glance
- Group/Class: Species
- Height × spread: 18 to 30 in (45 to 75 cm) × 12 to 18 in (30 to 45 cm)
- Bloom window: late spring to midsummer
- Color & flower form: pale to sky blue; five petaled, saucer shaped
- Fragrance: 0 none
- USDA hardiness: zones 4 to 8
- Breeder / Year / Origin: unknown; native to western North America
- Cut‑flower notes: Slender stems; research on perennial flax reports about 8 days with preservative for L. lewisii cuts.
- Pet safety: unknown
How it differs
- Native species; most seed mixes use the Eurasian Linum perenne.
- Often a bit taller than garden blue flax in lean mountain soils.
- Flowers are homostylous; L. perenne is usually heterostylous.
- Handles poorer soils and cold snaps in the interior West.
Strengths
- Cold and drought tolerant in sunny, well drained sites
- Reliable from fall or very early spring sowing
- Naturalizes lightly without running
- Minimal pest pressure in dry climates
Care in one minute
- Site: full sun with wind exposure for dry down after rain
- Soil: fast drainage; sandy or rocky loam; pH slightly acidic to moderately basic
- Water: light once established; deeper but infrequent soaks in drought
- Feeding: minimal; avoid high fertility that causes flop
- Grooming: deadhead to extend bloom; leave some pods to self sow; cut back in late winter
Watch‑outs
- Short lived; allow some seed set to maintain stands
- Can sprawl in rich or moist soil
- Rust may appear in wet springs
- Dislikes poor drainage or high water tables
Best uses (tags)
pollinators, meadows, slopes, rock gardens, low water borders
Provenance note
Named for Meriwether Lewis and described by Frederick Pursh in 1814 from Rocky Mountain material.
References
- NCSU Extension Plants: Linum lewisii
- USFS FEIS species review: Linum lewisii
- USU Extension Range Plants: Lewis flax
- ASHS HortScience 2022: Perennial Flax as a Cut Flower
Written by: Your Flowers Guide editorial team
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