Liriope muscari 'BIG BLUE' Monkey Grass, the most well known variety of Liriope, deep green foliage, lilac flower spikes, moderate spreader.
 
This ornamental grass has a clumping growth habit, and once mature can reach 12-15 in. tall. Liriope is very adaptable and can thrive in poor soils and dry conditions. Once established it is recommended to mow/trim back your liriope in fall so new fresh foliage can emerge in spring. 

Zone 5-11