Also known as a starflower, borage is an annual herb in the flowering plant family Boraginaceae. It is native to the Mediterranean region and has been naturalized in many other locales. The leaves are edible and the plant is grown in gardens for that purpose in some parts of Europe. The plant is also commercially cultivated for borage seed oil extracted from its seeds. Borago officinalis grows to a height of 60–100 cm (2.0–3.3 ft), and is bristly or hairy all over the stems and leaves; the leaves are alternate, simple, and 5–15 cm (2.0–5.9 in) long. The flowers are complete, perfect with five narrow, triangular-pointed petals. Flowers are most often blue, although pink flowers are sometimes observed. White flowered types are also cultivated. The blue flower is genetically dominant over the white flower. The flowers arise along scorpioid cymes to form large floral displays with multiple flowers blooming simultaneously, suggesting that borage has a high degree of geitonogamy (intra-plant pollination). It has an indeterminate growth habit which may lead to prolific spreading. In temperate climate such as in the UK, its flowering season is relatively long, from June to September. In milder climates, borage will bloom continuously for most of the year.
The seeds contain 26-38% of borage seed oil, of which 17-28% is gamma-linolenic acid (GLA), the richest known source. The oil also contains the fatty acids palmitic acid (10-11%), stearic acid (3.5-4.5%), oleic acid (16-20%), linoleic acid (35-38%), eicosenoic acid (3.5-5.5%), erucic acid (1.5-3.5%), and nervonic acid (1.5%). The oil extracted from borage seeds is often marketed as “starflower oil” or “borage oil” for use as a GLA supplement.
Products and Uses
Borage flower and leaves are used for fever, cough, and depression. Borage is also used for a hormone problem called adrenal insufficiency, for “blood purification,” to increase urine flow, to prevent inflammation of the lungs, as a sedative, and to promote sweating. Borage is also used to increase breast milk production and to treat bronchitis and colds. Borage is applied to the skin for infantile seborrheic dermatitis and is also used in a dressing to soften the skin. In foods, borage is eaten in salads and soups. In manufacturing, borage is used in skin care products.