Crested Hairgrass (Koeleria macrantha) is a perennial grass of a compact, tufted nature. It is found on dry grasslands, favouring calcareous, limestone and chalk soils. It has narrow, green/grey leaves and clustered flower heads which are silvery green to purple in colour. It reaches around 40cm in height. It can be sown at any time of the year when conditions are suitable and survives well in low nutrient, stress environments.