Poa poiformis, commonly known as coast tussock-grass or blue tussock-grass, is a densely tufted, erect, perennial tussock grass, with distinctive blue-green leaves, that grows to about 1 m in height.

In botany, the term perennial is used to differentiate a plant from shorter-lived annuals and biennials. It has thus been defined as a plant that lives more than 2 years. The term is also loosely used