Agrostis gigantea Roth
Agrostis gigantea, commonly known as black bent, redtop, is a grass.
Agrostis gigantea was described by Albrecht Wilhelm Roth in 1788. The name is considered as validly published.
The comparatively fast-growing and short-lived grasses have a decumbent habit and reach heights of 1 to 1,3 metres. They spread rapidly, the main growing season is in spring and summer.
Agrostis gigantea is deciduous. The dark-green, simple leaves are alternate. They are linear with entire margins and parallel venation. The foliage is dense in summer and porous in winter.
Flowers and Fruits
Agrostis gigantea produces white-yellow flowers from June to August.
The grasses produce an abundance of brown caryopses in summer.
The plants produce rhizomes which give rise to vegetative spread.
Agrostis gigantea is native to the whole of Europe, Turkey, Iraq, the Caucasus, Iran, West-Siberia, East Siberia, Afghanistan, Pakistan, Northwest India, Mongolia, China, Morocco and Algeria and is naturalized in North America, Central America, South America, South Africa, Lesotho and Swaziland, Australia and New Zealand.
The grasses prefer a sunny situation on moderately moist soil. The substrate should be comparatively poor with a pH between 4,5 and 8. The plants need a soil depth of at least 36 centimetres for good growth. They tolerate temperatures down to -35Â°C (USDA zone 4) and need a frost-free period of at least 13 weeks.
Tolerance of special soil conditions
- low: soil salinity, drought, calcareous soil
- medium: anaerobic soil
Maintenance and Propagation
Propagate by sowing.
Pests and Diseases
- Walter Erhardt, Erich GÃ¶tz, Nils BÃ¶deker, Siegmund Seybold: Der groÃe Zander. Eugen Ulmer KG, Stuttgart 2008, ISBN 978-3-8001-5406-7. (Ger.)
- Christoper Brickell (Editor-in-chief): RHS A-Z Encyclopedia of Garden Plants. Third edition. Dorling Kindersley, London 2003, ISBN 0-7513-3738-2.