A perfect plant for medium to full shade conditions, Ophiopogon japonicus, also known as mondo grass, is a great filler for containers and beds. It's a useful groundcover, and is ideal to use bordering paths, in the front of borders, and in rock gardens. Black mondo grass ( Ophiopogon planiscapus 'Nigrescens') doesn't spread quickly, so it's better used as a specimen where you can appreciate its unusual color up close.
Colors: Mondo grass has 8- to 12-inch-long strappy dark green leaves; short spikes of lilac flowers aren't notable. Black mondo grass has green-maturing-to-ebony leaves that reach 14 inches long, and white flowers.
Size: Dense clumps reach 6 to 8 inches high about a foot wide. Mondo grass spreads by underground stems.
Care: Mondo grass likes part to full shade, and regular water. If plants start looking ragged, mow or shear before new growth beings in spring. Divide when clumps become overgrown, and replant divisions 6 to 8 inches apart.
Planting: Plant mondo grass from spring through fall in well-drained soil.
Companions: Plant with ferns, impatiens, liriope, and begonia; black mondo grass is especially showy next to light colored foliage like Acorus gramineus 'Ogon', blue fescue, and lime or bronze heuchera.