Cortaderia is a genus of grass in the family Poaceae, comprising about 20-25 species, with about 15-20 species native to South America, four species in New Zealand and one in New Guinea. The species is commonly known as Pampas Grass or Tussock Grass.
Cortaderia species are inposing tall grasses, 1.5-3 m tall, evergreen and have graceful white inflorescence plumes. The long, arching, mid-green leaves make a dense clump, from which arise the erect stems of silvery flowerheads in autumn, and the grass is a striking feature in winter garden.
Cortaderia selloana (Pampas Grass), 3 x 1.5 m, is a tall grass native to southern South America and Patagonia. The species is named after a German botanist and naturalist Friedrich Sellow (1789-1831), one of the earliest scientific explorers of the Brazilian flora. Cortaderia selloana can grow to a height of three meters, forming dense tussocks. The leaves are evergreen, long and slender, 1-2 m long and 1 cm wide, with very sharp edges. The leaves are usually bluish-green, but silvery grey can also be found. The white flowers are borne on a tall stem of 2-3 m, in a dense panicle of 20-40 cm. This grass is highly adaptable and can grow in a wide range of environment and climates. In areas such as California, Hawaii and Spain, it is considered an invasive weed as the grass seeds prolifically, with each plant able to produce over one million of seeds. Romoval of Pampas Grass by burning will not always prevent return. Chemical weed killer will kill the grass at the roots.
Cortaderia jubata (Purple Pampas Grass, Andean Pampas Grass) is a tall grass native to the northern Andes, but it is famous as a noxious weed in California, where it is first introduced as an attractive ornamental plant. It can grow to a height of up to seven meters, and has leaves that are long, thin with razor-sharp edges. The leaves form a large tussock from which a tall stem of several meters is borne. At the top of the stem, a panicles of eye-catching inflorescence is produced, which are pink or purplish when new and gradually turn to cream or white color. Each inflorescence is packed full with seeds which are developed despite the plant having never been fertilized. The grass has only pistillate parts, which means all individuals are female, and reproduces by apomixis, in which the embryos develop without fetilization. The seeds are dispersed via wind, water, and soil transport.
Several smaller cultivars are available, such as 'Pumila' which grows to 1.5 x 1.2 m tall and broad, with mid-green leaves and silver-yellow plumes. 'Aureolinata' , also known as 'Gold Band', can grows up to 2.1 m tall, has yellow-green leaves that mature to golden yellow. One of the most attractive cultivars, 'Sunningdale Silver', 3 x 2.4 m tall and broad, has dense silver-white plumes borne on sturdy erect stems. Wear strong gloves whenever removing dead leaves in early winter or early spring because the leaves have sharp edges.
Cortaderia species is easy to grow and grows well in sun, in fertile and well-drained soil. Propagation is by seeds or divide in spring.
Cortaderia jubata http://commons.wikimedia.org/wiki/File:Cortaderiajubata.jpg Gordon Leppig & Andrea J. Pickart
Cortaderia jubata http://commons.wikimedia.org/wiki/File:Starr_050815-3362_Cortaderia_jubata.jpg Forest & Kim Starr
Cortaderia jubata http://commons.wikimedia.org/wiki/File:Starr_050815-3360_Cortaderia_jubata.jpg Forest & Kim Starr
http://commons.wikimedia.org/wiki/File:Cortaderiajubata.jpg
Gordon Leppig & Andrea J. Pickart
