Purple moor grass is an upright, warm season perennial grass that has dense, flat narrow leaf blades that grow from 1-2ft tall. Leaf blades emerge green in spring, thin, white and green flowers have a purplish tone, but rapidly fades to brown as the seed sets after flowering. Flower stalks and the foliage turn yellow to orange yellow, eventually fading into light tan. 3ft upright to arching, wispy flower stalks are topped with narrow flower panicles that rise above the foliage in mid-summer.

Molina caerulea is separated into two subspecies. Subspecies caerulea which is moor grass with its grass clump being 18” tall and the flower stalks being 2-3’ tall; and subspecies arundinacea which is the tall moor grass that has a mounded grass clump being 3’ tall, with flower stalks pushing upwards of 6-8’ tall.