Royal purple liriope, commonly called lilyturf or monkey grass, is a tufted tuberous-rooted grass-like perennial which features clumps of strap-like, arching, glossy, dark green leaves. Clumps spread slowly and expand but do not spread aggressively like liriope spicata. Showy flower spikes with dark purple flowers rise above the leaves in late summer. Flowers can give way to blackish berries which often persist into winter.