Cornflower, Garden cornflower, Blue Bottle, Cornflower
Centaurea cyanus
Family: Asteraceae or Compositae
What it is like
Bloom Color: Blue, Lavender, Pink, Purple, White. Main Bloom Time: Early summer, Early fall, Late summer, Mid summer. Form: Upright or erect.
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.
Height (m): 1
Where it is found
Once a common weed of cornfields, as a result of modern agricultural practices it is now very rare in the wild. Found especially on porous, nutrient-rich soils.
Most of Europe, including Britain, to the Near East.
Conservation Status: This taxon has not yet been assessed. Possibly endangered in its native habitat by agricultural intensification, particularly over-use of herbicides, destroying its habitat.
Countries/locations it is found in
Asia, Australia, Britain, Europe, Hawaii, India, Mediterranean*, North America, Pacific, Poland, Tasmania, Turkey, USA, Yugoslavia.
How it is used
Food
Rating: 2
The young shoots are edible. Flowers - raw or cooked. The fresh florets can be used in salads. They are used as a vegetable or a garnish. An edible blue dye is obtained from the flowers, used for colouring sugar and confections.
Colouring: edible dyes
Medicine
Rating: 2
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. Traditionally it is said to work best on blue eyes, whilst Plantago major (great plantain) was used for brown eyes. The dried flowers are antipruritic, antitussive, astringent, weakly diuretic, emmenagogue, ophthalmic, very mildly purgative, and tonic. An infusion can be used in the treatment of dropsy, constipation, or as a mouthwash for ulcers and bleeding gums. 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. A water distilled from the petals was formerly in repute as a remedy for weak eyes and a soothing lotion for conjunctivitis. The seeds are used as a mild laxative for children. A decoction of the leaves is antirheumatic. Antifungal .
Antifungal: An agent that inhibits or destroys fungi. Used in the treatment of various fungal problems such as candida.
Antipruritic: Treats itching of the skin.
Antirheumatic: Treats rheumatism.
Antitussive: Prevents or relieves coughing.
Astringent: Produces contraction in living tissue, reducing the flow of secretions and discharges of blood, mucus, diarrhoea etc.
Diuretic: Acts on the kidneys, promoting the flow of urine.
Emmenagogue: Promotes or increases the menstrual flow. In early stages of pregnancy it can induce an abortion.
Laxative: Stimulates bowel movements in a fairly gentle manner.
Ophthalmic: Treats eye complaints.
Purgative: A drastic laxative causing a cleansing or watery evacuation of the bowels, usually with a griping pain.
Tonic: Improves general health. Slower acting than a stimulant, it brings steady improvement.
Other
Rating: 2
A blue ink and a dye is obtained from the petals mixed with alum-water. The dye gives a lovely colour to linen, but it is transient. The dried petals are used in pot-pourri in order to add colour. Extracts of the plant are added to hair shampoos and rinses. Grown as an ornamental plant in gardens and as a cutflower in Canada for florists.
Dye: Plants that provide dyes.
Hair: Plants used as hair shampoos, tonics, to treat balding etc.
Ink: Plants that can be used as an ink.
Pot-pourri: Aromatic plants used to impart a pleasant smell to an area. Can this be grouped with incense or essential oil?
Attracts Wildlife: Plants noted for attracting wildlife
How it is grown
Landscape Uses:Border, Container, Foundation, Massing, Seashore, Specimen. Succeeds in ordinary garden soil. Prefers a well-drained fertile soil and a sunny position. Tolerates dry, low fertility and alkaline soils. Established plants are drought tolerant. A very ornamental plant, there are many named varieties. The flowers are often used in dried-flower arrangements because they retain their colour well. A good plant for bees, butterflies and moths. The cornflower is considered to be a good companion, in small quantities, for cereal crops, though another report says that its greedy roots deprive the cultivated plants of nutrients and its tough stem dulls the reaper's sickle. Members of this genus are rarely if ever troubled by browsing deer. Special Features: Not North American native, Invasive, Naturalizing, Suitable for cut flowers, Suitable for dried flowers.
Propagating it: Seed - sow March in the greenhouse. When they are large enough to handle, prick the seedlings out into individual pots and plant them out in May. The seed can also be sown in situ during April, whilst in areas where the winters are not too cold a sowing in situ during September will produce larger and earlier-flowering plants
Best place to grow: Cultivated Beds;
Habit: Annual
Hardiness: 0-0
Growth: Fast
Soil: Light (sandy), medium, heavy (clay)
Shade: No shade
Moisture: Dry, moist
Things to keep in mind
This plant can be weedy or invasive.
Its other names
Local names
Bachelor's button, cornflower, garden cornflower, boutonniere flower, hurtsickle, Bluebottle, or cyani flower,.