Arrhenatherum elatius subsp. bulbosum, commonly known as Tuber Oat Grass, Onion Couch, or Tall Bulbous Oatgrass, is a perennial grass native to a variety of habitats including meadows, grasslands, roadsides, and disturbed areas across North Africa, Asia and particularly in Europe. It typically grows at a moderate rate to a height of 1.5-3 feet (0.46-0.9 meters) and features a tufted habit with erect, slender stems. The leaves are flat and linear, contributing to its grassy texture. Its flowers are green or yellow and are considered inconspicuous, blooming in the summer. The plant is not particularly known for its flowers but rather for its foliage and form.

Tuber Oat Grass is appreciated for its adaptability and is used for ornamental purposes in garden borders, as ground cover, and in naturalized areas. It is also valued for its ability to thrive in a range of soil types, including clay, loam, and sandy soils, provided they have medium or fast drainage. It requires medium amounts of water and can grow in full sun to part shade. While it is not known for significant pest or disease problems, its potential for invasiveness should be considered before planting, as it can spread aggressively outside its native range. Gardeners should check local regulations and guidelines to ensure it is not a problematic species in their area.CC BY-SA 4.0