Centaurea montana (perennial cornflower)
Detail of an illustration of Centaurea montana
Centaurea montana L.
perennial cornflower, mountain blue, perennial bachelor’s button, mountain cornflower
Subalpine meadows and open woods.
About this species
This low-growing perennial is widespread across much of central and southern Europe, and although not native to Britain is now naturalised in many parts of the British Isles. Centaurea montana has been grown in English gardens for centuries, and is a useful, if somewhat untidy, addition to a herbaceous border. It was probably introduced to Britain from elsewhere in Europe at some point during the 16th century.
The herbalist John Gerard certainly had it in his garden, and described ‘the great Blew-Bottle’ in his herbal of 1597, although he admitted that ‘the faculties of these floures are not sufficiently known’, implying, perhaps, that he had not grown it for long. In 1790, William Curtis, writing in Curtis’s Botanical Magazine, still called this the ‘Greater Blue-Bottle’, a plant that ‘will grow in any soil or situation, some will think too readily’.
Geography and distribution
Native to Europe, from Belgium eastwards to Poland and Serbia, and south to the Spanish Pyrenees; in subalpine meadows and woods. It has become naturalised elsewhere in Europe and in North America.
A low-growing perennial, with creeping rhizomes (underground stems), forming spreading patches. The stems are up to 60 cm tall and bear lance-shaped, undivided, leaves, which are cottony on the underside. The flowerheads are up to about 5 cm across, opening from May to July. They are usually large and blue, with deeply cut florets, but can vary in colour. Cultivars include Centaurea montana ‘Alba’ (with white flowerheads), ‘Carnea’ (with pink flowerheads) and ‘Violetta’ (with mauve flowerheads).
Illustration from Curtis’s Botanical Magazine
Curtis’s Botanical Magazine (Editor: Martyn Rix) provides an international forum of particular interest to botanists and horticulturists, plant ecologists and those with a special interest in botanical illustration.
Now well over 200 years old, the Magazine is the longest running botanical periodical featuring colour illustrations of plants. Each four-part volume contains 24 plant portraits reproduced from watercolour originals by leading international botanical artists. Detailed but accessible articles combine horticultural and botanical information, history, conservation and economic uses of the plants described.
Published for the Royal Botanic Gardens, Kew by Wiley-Blackwell Publishing.
A bitter tea made from the plant was traditionally used to treat dyspepsia and as a diuretic. Perennial cornflower is cultivated as an ornamental and is suitable for a herbaceous border, woodland garden or large rock garden.
Millennium Seed Bank: Seed storage
The Millennium Seed Bank Partnership aims to save plant life worldwide, focusing on plants under threat and those of most use in the future. Seeds are dried, packaged and stored at a sub-zero temperature in Kew's seed bank vault at Wakehurst.
Description of seeds: Average 1,000 seed weight = 15.5 g
Collections stored in the Millennium Seed Bank: None
Composition values: Average oil content = 22%. Average protein content = 21.2%.
Perennial cornflower grows well in moist but well-drained soil, in sun or partial shade. It can be propagated by division. Flowerheads are produced in early summer
This species at Kew
Centaurea montana can be seen growing in the Rock Garden at Kew and in The Slips at Wakehurst.
Pressed and dried specimens of Centaurea species are held in Kew’s Herbarium, where they are available to researchers, by appointment. The details, including images, of some of these can be seen online in the Herbarium Catalogue.
Curtis, S. (1790). Centaurea montana. Curtis’s Bot. Mag. 3: tab. 77.
Gerard, John (1597). The Second Booke of the Historie of Plants, (commonly called Gerard's Herbal): 251, as 'The great Blew-Bottle'. Studio editions reprint 1994, London.
Phillips, R. & Rix, M. (1991). Perennials, Volume 2. Pan Books.
Royal Botanic Gardens Kew. (2008) Seed Information Database (SID). Version 7.1. Available online (accessed 11 April 2011).
Schauenberg, P. & Paris, F. (1977). Guide to Medicinal Plants. Lutterworth Press, Guildford & London.
Stace, C. (1997). New Flora of the British Isles. Cambridge University Press, Cambridge.
The Plant List (2010). Centaurea montana. Available online (accessed 08 April 2011).
Kew Science Editor: Martyn Rix
Kew contributors: Steve Davis (Sustainable Uses Group)
Copyediting: Emma Tredwell
While every effort has been taken to ensure that the information contained in these pages is reliable and complete, the notes on hazards, edibility and suchlike included here are recorded information and do not constitute recommendations. No responsibility will be taken for readers’ own actions.