Linum (flax) is a genus of approximately 200 species in the flowering plant family Linaceae, native to temperate and subtropical regions of the world. It includes the Common Flax (L. usitatissimum), the bast fibre of which is used to produce linen and the seeds to produce linseed oil.
The flowers of most species are blue or yellow, rarely red, white, or pink, and some are heterostylous. There is an average of 6-10 seeds per boll.
Linum species are used as food plants by the larvae of some Lepidoptera species including Cabbage Moth, The Nutmeg, Setaceous Hebrew Character and Coleophora benedictella, which feeds exclusively on Linum narbonense.
Several flaxes are cultivated as garden ornamentals, including the blue-flowered species Linum lewisii, L. perenne, and L. narbonense, red-flowered L. grandiflorum, and yellow-flowered L. flavum.