Windmill grass can be either annual or short term perennial and forms a rounded tussock usually less than 50 cm tall. The stems are smooth with two to three nodes towards the base, which may form roots at the nodes. The roots at the nodes enable the plant to spread across the soil surface. The leaves are flat, without hairs and are rough to the touch. They are up to 14 cm long and two to five centimetres wide. Windmill grass flowers from late winter to summer with flower heads that have six to nine spikes all spreading out from a common point forming an umbrella shape.