Molinia caerulea, known by the common name purple moor-grass, is a species of grass that is native to Europe, west Asia, and north Africa. It grows in locations from the lowlands up to 2,300 m (7,546 ft) in the Alps. Like most grasses, it grows best in acid soils, ideally pH values of between 3.5 and 5, however, it can continue to live under more extreme conditions, sometimes to as low as 2. It is common on moist heathland, bogs and moorland throughout Britain and Ireland. Introduced populations exist in northeastern and northwestern North America.
The specific epithet caerulea means "deep blue" and refers to the purple spikelets.
Molinia caerulea is a herbaceous perennial bunchgrass (tussock-forming), growing up to 120 cm (47 in) tall (taller when sheltered by gorse and heather), with many closely packed stems. The leaves are coarse, green, taper to a point, long, flat and sometimes slightly hairy on top. Due to the dense tussock it is very resistant to heath fires. Its ligule is a ring of hairs, as in heath grass (Danthonia decumbens). The long narrow purple spikelets are a major identification feature – the panicle is 15 cm (6 in) long.
It flowers between July and September, later than any other species.
The caterpillars of some Lepidoptera use it as a foodplant, e.g., the chequered skipper (Carterocephalus palaemon).
Claviceps purpurea is an ascomycetous fungus which grows on the seeds of purple moor grass.
Purple moor grass and rush pastures is a United Kingdom Biodiversity Action Plan habitat, on account of its rarity.
Molinia caerulea is cultivated for its panicles of purple spikelets on yellow stems. In cultivation it grows to 1.5 m (5 ft) tall by 40 cm (16 in) broad. Numerous cultivars have been selected, of which the following have gained the Royal Horticultural Society's Award of Garden Merit:
- M. caerulea subsp. arundinacea 'Windspiel'
- M. caerulea subsp. caerulea 'Edith Dudszus'
- M. caerulea subsp. caerulea 'Moorhexe'
- M. caerulea subsp. caerulea 'Poul Petersen'
- M. caerulea subsp. caerulea 'Variegata'
Sclerotium of Claviceps purpurea which grows on the seeds of purple moor grass.
- ^ BSBI List 2007 (xls). Botanical Society of Britain and Ireland. Archived from the original (xls) on 2015-06-26. Retrieved 2014-10-17.
- ^ Molinia caerulea (L.) Moench
- ^ Harrison, Lorraine (2012). RHS Latin for gardeners. United Kingdom: Mitchell Beazley. p. 224. ISBN 9781845337315.
- ^ Grasses by C E Hubbard, 1978, published by Penguin books
- ^ Cope, Tom; Gray, Alan (2009). Grasses of the British Isles. London: Botanical Society of the British Isles.
- ^ UK BAP Purple Moor and Rush Pastures Archived 2007-12-06 at the Wayback Machine
- ^ RHS A-Z encyclopedia of garden plants. United Kingdom: Dorling Kindersley. 2008. p. 1136. ISBN 978-1405332965.
- ^ "AGM Plants - Ornamental" (PDF). Royal Horticultural Society. July 2017. p. 65. Retrieved 4 April 2018.
- ^ "RHS Plantfinder - M. caerulea subsp. arundinacea 'Windspiel'". Retrieved 4 April 2018.
- ^ "M. caerulea subsp. caerulea 'Edith Dudszus'". RHS. Retrieved 6 January 2021.
- ^ "RHS Plantfinder - *M. caerulea subsp. caerulea 'Moorhexe". Retrieved 4 April 2018.
- ^ "Molinia caerulea subsp. caerulea 'Poul Petersen'". RHS. Retrieved 6 January 2021.
- ^ "RHS Plant Selector - Molinia caerulea subsp. caerulea 'Variegata'". Retrieved 24 May 2013.
- Fitter, Richard; Fitter, Alastair; Farrer, Ann (1984). Grasses, Sedges, Rushes and Ferns of Britain and Northern Europe. Collins Pocket Guides. Collins. ISBN 0002191369.
- Rose, Frances (1974). The Observer's Book of Grasses, Sedges and Rushes. Frederick Warne & Co. pp. 18–19.
- Noyes, Alfred (16 September 2021). "The Highwayman".