Plant library · Groundcovers
Ophiopogon japonicus
Mondo grass is a low, evergreen perennial groundcover that brings a neat, tufted line to shaded planting areas. At roughly 9 inches tall and 1 foot wide, it stays below most border plants while giving beds a continuous green base. Use its fine, grass-like texture to settle the visual edge of a planting without creating a tall barrier or hiding nearby features.
Place mondo grass along the front of a partially shaded border, beside a patio, or at the base of shrubs where a low evergreen layer will clarify the edge. It also suits small lawn-alternative areas, but lay out a defined planting zone rather than treating it as a route through the garden. Keep it on the bed side of paths and stepping areas so its low foliage can soften hard edges without narrowing circulation.
Space plants 9 inches apart, center to center, for an interlocking groundcover pattern. Each clump can occupy about 1 foot of width at maturity, so allow the planting to read as a low, continuous band rather than a row of isolated tufts. For a border beside a path, set the planting line back enough that the mature foliage remains within the bed and the full path width stays clear.
Use this groundcover in partial shade, where regular watering can keep the planting even and green. Moist, well-drained soil supports a dense, orderly cover; avoid placing it where water collects after rain or where soil repeatedly dries hard beneath shallow-rooted trees. Group it with other plants that can share regular moisture, rather than pairing it with a dry gravel-style planting.[1][2]
Summer brings small flowers, but the planting works chiefly as an evergreen ground layer rather than a seasonal floral display. Its persistent foliage makes it useful for holding the outline of borders and path edges through quieter parts of the year. Leave enough open space around specimen plants and garden ornaments so the low cover frames them instead of visually merging with every feature.[1][2]
In colder parts of Zone 6, choose a protected location rather than an exposed, wind-swept edge. Winter foliage can look worn after severe weather, so avoid relying on it as the only crisp structural element beside a highly visible entrance or formal walk. Reserve a little access from the path or bed edge for cleanup and for dividing established clumps when the planting needs adjustment.[2]
Editorial content updated 2026-07-20.