Cornflower, Garden cornflower, Blue Bottle, Cornflower

Centaurea cyanus

Physical Characteristics

Centaurea cyanus is a ANNUAL growing to 1 m (3ft 3in) by 0.3 m (1ft) at a fast rate. It is not frost tender. It is in flower from June to August, and the seeds ripen from August to October. The species is hermaphrodite (has both male and female organs) and is pollinated by Bees, flies, Lepidoptera (Moths & Butterflies). The plant is self-fertile. It is noted for attracting wildlife. Suitable for: light (sandy), medium (loamy) and heavy (clay) soils, prefers well-drained soil and can grow in nutritionally poor soil. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils and can grow in very alkaline soils. It cannot grow in the shade. It prefers dry or moist soil and can tolerate drought.

Distribution

Most of Europe, including Britain, to the Near East.

Habitats

Cultivated Beds;

Edible Uses

Edible Parts: Flowers Shoots Edible Uses: Colouring The young shoots are edible[7]. Flowers - raw or cooked. The fresh florets can be used in salads[238]. They are used as a vegetable or a garnish[183]. An edible blue dye is obtained from the flowers, used for colouring sugar and confections[183].

Medicinal Uses

Antifungal Antipruritic Antirheumatic Antitussive Astringent Diuretic Emmenagogue Laxative Ophthalmic Purgative Tonic Cornflower has a long history of herbal use, though it is seldom employed nowadays. In France it is still used as a remedy for tired eyes, but opinions differ as to its efficacy[254, 268]. Traditionally it is said to work best on blue eyes, whilst Plantago major (great plantain) was used for brown eyes[268]. The dried flowers are antipruritic, antitussive, astringent, weakly diuretic, emmenagogue, ophthalmic, very mildly purgative, and tonic[4, 7, 9, 21, 201, 240]. An infusion can be used in the treatment of dropsy, constipation, or as a mouthwash for ulcers and bleeding gums[9, 238]. This infusion is also taken as a bitter tonic and stimulant, improving the digestion and possibly supporting the liver as well as improving resistance to infections[254]. A water distilled from the petals was formerly in repute as a remedy for weak eyes[4] and a soothing lotion for conjunctivitis[7, 240]. The seeds are used as a mild laxative for children[7, 254]. A decoction of the leaves is antirheumatic[7, 254]. Antifungal [303].

Known Hazards

None known