Mondo grass, with its dark green leaves and striking appearance, is a versatile and hardy groundcover that makes an eye-catching border, lawn alternative, or specimen plant. Native to Southeast Asia, these ornamental grasses belong to the lily family and are often mistaken for Liriope due to their similar look and growth habits.
With varieties like Ophiopogon japonicus ‘Nana’ offering compact, light green mounds and the unique black-leafed cultivars bringing dramatic flair, mondo grass thrives in partial shade. This plant is also drought-tolerant, deer-resistant, and well-suited to different hardiness zones, making it a solid choice for both garden beds and patios.
Whether you’re planting mondo grass or incorporating it as a houseplant, you’ll appreciate that it’s low maintenance. The lilac or white flowers that appear in the summer add a touch of elegance, while its mounding growth habit helps create a lush, full look in any landscape. With proper watering and occasional mowing to keep it neat, mondo grass can transform your outdoor space into a green oasis.
Easy to propagate and tolerant of a wide range of conditions, it’s a good choice for beginning gardeners. When considering mondo grass, there are several types to choose from. Each one giving you different results. In this article, I’ll walk you through the different types of mondo grass and how to care for them, helping you choose the perfect option for your outdoor space.
Mondo Grass Basics
The term “mondo grass” refers to several species of evergreen perennial groundcovers native to Southeast Asia. They look like grasses, but they’re actually members of the lily family (Liliaceae). In some more recent classifications, they are classified as members of the asparagus family (Asparagaceae). The plant grows in clumps and spreads by sending out underground stolons (runners) and rhizomes (tuberous roots), but you can also propagate it by division.
Mondo grass (Ophiopogon genus) is often confused with Liriope (Liriope genus) because plants in the two groups are so similar in appearance and growth habits. The common names “monkey grass” and “lilyturf” are used for plants in both genera. To make sure you get the plant you want, always check the Latin botanical name. Three types of mondo grass are commonly available.
Mondo grass (Ophiopogon Japonicus) — The standard and most common mondo grass variety, this plant averages around 6 to 10 inches high and can reach 15 inches across. In summer, stalks of tiny, bell-shaped lavender flowers rise from its deep green leaves and produce a faint, sweet scent. The flowers are followed by cobalt blue berries. This plant does well in USDA zones 7 to 10 and is cold-hardy down to -10 degrees. Even in near-freezing weather, its leaves stay green. While it can survive milder winters in zone 6, it won’t make it through colder ones.
Dwarf mondo grass (Ophiopogon Japonicus ‘Nanus’) — This small variety grows between 4 to 6 inches tall and around 8 inches wide. It puts out white or lavender flowers and blue berries. Beyond its size and flower color, it’s otherwise similar to standard mondo grass.
Black mondo grass (Ophiopogon planiscapus ‘Nigrescens’) — Although it’s a different species from standard mondo grass, this plant has similar growth habits and care requirements. It’s best known for the purplish-black color of its leaves, but the pink flowers it produces are an added benefit. It’s also larger than the other common mondo grass varieties, growing up to 12 inches high and 12 to 24 inches across.
Giving Mondo Grass a Place in Your Garden
Mondo grass owes a large part of its popularity to the variety of ways it can be used. For dwarf mondo grass, groundcover is the most common use. It’s an ideal lawn alternative if you want lush green grounds without the hassle of maintaining turf grass. Once a few plants are in place, they spread to create a lawn-like cover. This variety is a notoriously slow grower, though, so your lawn will take a few years to fill in.
It’s perfect for areas of deep shade and can even grow under black walnut trees. It’s also well suited to slopes where grass doesn’t grow well. Mondo grass is a traditional groundcover in Japanese gardens, where it’s planted around stepping stones and statues, under trees, and in flowing shapes around gravel beds.
Because it stops growing at a low height, you won’t need to — and, in fact, you shouldn’t — mow it. The downside is that mondo grass is more delicate than turf grass.
Dwarf mondo grass can tolerate being walked on every now and then, but regular foot traffic will destroy it. If you need to walk through an area planted with mondo grass, install stepping stones or another type of path.
The plant is fairly pet-friendly. While it can stand up to dogs running and playing, it doesn’t handle their digging or urinating as easily. That said, it still tends to fare better than most turf grass.
Because it’s small and slow-growing, dwarf mondo grass performs well as a houseplant. Plant it in well-draining potting soil or potting mix and place it in a shady or partially shady spot.
Standard-sized and black mondo grass often serve as ornamental plants. As edging plants, they create soft, informal borders between garden beds and the lawn or walkways. Their medium height helps them hold back plants in a planting bed without overwhelming them. If you need an edge wider and higher than what strip or masonry edging provides, mondo grass fits the bill perfectly.
As an ornamental plant, mondo grass adds a fountain of deeply colored leaves and produces a soothing rustling sound in the wind, making it a pleasant addition to seating areas. Although the flowers tend to get lost among the leaves, they don’t serve as the main reason to grow the plant.
Mondo grass varieties tolerate salt well, which allows them to thrive in coastal gardens. The plant thrives in the shade of trees and resists deer, making it a great choice for gardens in forested areas.
Mondo Grass Care Requirements
Mondo grass is easy to care for once established, but getting it established takes some preparation. In most climates, it can grow in anything between full sun to full shade, but it thrives in filtered sunlight. The more sun the plant gets, the lighter the leaf color will be. In a hot climate, though, a shady location is a must. Choose a location with well-draining soil or improve the soil drainage by working in three or four inches of organic matter, such as compost or well-rotted manure.
You can grow the plant from seed, but most gardeners buy packs of plugs for a quicker start. Plant small plug plants as they are. If you propagate a larger plant, separate it into groups of two to four stolons. Space standard and black mondo grass 6 to 12 inches apart, and dwarf mondo grass 2 to 4 inches apart, depending on how quickly you want to cover the area. By dividing the plant, you can create an entire border from just one plant, though it will take years.
The only thing mondo grass is truly picky about is watering. Water it when the soil becomes dry down to 1 inch, which is usually once or twice a week in a moderate climate. Aim to keep the soil slightly moist during dry weather, but don’t let it become oversaturated because this plant doesn’t appreciate soggy feet. In general, mondo grass tolerates under-watering better than overwatering.
Mondo grass needs little fertilizing and often does well with none at all. It’s usually enough to apply a slow-release 10-10-10 fertilizer formulated for trees and shrubs once a year in early spring.
Mondo grass isn’t especially prone to pests or disease, but watch out for slugs and snails in damp, cool periods and fungal infections in damp, warm periods. Root rot, caused by the pathogen Pythium splendens, is one of the most common problems and brown leaf tips are usually the first sign. You might also notice the top of the plant is easy to pull away from the roots. To treat the condition, apply a fungicide formulated for this pathogen and topdress the soil with organic matter.
In spring, trim off any dead or broken leaves to keep the plant looking neat.
This plant spreads slowly, but it does spread, so you’ll need to do a little work to keep it in check. To keep it in a defined area, install strip edging or other edging material around it. For single plants or small groups, control their size by dividing the clump every three or four years in early spring. To do this, dig up the plant, taking care to unearth as many of its tuberous roots as you can, and gently pull the clump apart. Replant the new clumps where you want them. To corral daughter plants that have sprung up outside the main planting area, simply dig them up and replant them elsewhere.
Mondo grass isn’t a slow-grower everywhere, though. In the warm, humid Southern U.S., it flourishes so well it can easily become invasive. If you live in the South, I recommend talking with a plant nursery worker about mondo grass’ growth habits in your area.
As a lawn alternative, dwarf mondo grass can give you a lush expanse of green with less effort than turf grass and many other groundcovers. Standard and black mondo grass work well for a garden bed border that’s striking enough to stand out, but won’t detract from your flowers. Even a single mondo grass plant in an urn planter can dress up a dull corner of the garden.
Start your mondo grass off with the right light and soil conditions, take care with watering, and the plants should do well with minimal extra attention.
Final Thoughts
Mondo grass really is a fantastic choice for adding a lush, green touch to your garden or patio. It can serve as a groundcover, lawn alternative, or a striking border plant. Mondo grass is also known for its resilience, tolerating drought and deer while adding elegance with its subtle flowers.
The varied colors offer something for every garden space. Its rich green leaves and striking black varieties add a unique touch, while its adaptability to different light conditions makes it versatile. As a low-maintenance plant, mondo grass not only looks great but is also easy to care for. By choosing mondo grass and giving it the right care, you’ll enjoy its vibrant, lush groundcover all year-round.
Frequently Asked Questions
Does mondo grass like sun or shade?
Mondo grass thrives in various light conditions depending on the variety. Green varieties adapt well to full sun or shade, with leaf color changing accordingly, while black varieties need full sun to maintain their dark hue.
Will mondo grass spread?
Yes, mondo grass will spread, though it does so at different rates depending on the variety. Tall varieties spread quickly once established, while dwarf varieties spread more slowly.
How often should I water mondo grass?
Water newly planted mondo grass a few times a week to help it establish, then switch to once a week for mature plants, adjusting based on soil dryness and climate.
