Linum perenne, the perennial flax,<ref name=BSBI07>Template:Cite web</ref> blue flax or lint, is flowering plant in the family Linaceae, native to Europe, primarily in the Alps and locally in England.
The English populations are sometimes distinguished as Linum perenne subsp. anglicum and high altitude populations in the Alps as Linum perenne subsp. alpinum. The similar western North American species Linum lewisii is sometimes treated as a subspecies of L. perenne.
Cultivars for garden use include 'Blue Sapphire'.
- Blamey, M. & Grey-Wilson, C. (1989). Illustrated Flora of Britain and Northern Europe. Hodder & Stoughton.
- Huxley, A. (1992). New RHS Dictionary of Gardening vol. 3: 93. Macmillan.