The Complete Guide To Mondo Grass – How To Grow and Care For

Mondo Grass isn’t a true grass. It’s an evergreen in the same family as lily and asparagus, so it is much easier to grow than true grasses. Also known as Monkey Grass, this grass-alternative forms mounds and spreads using underground runners, helping it fill in and suppress many weeds. Whether you need a resilient turf-alternative, a low-maintenance ornamental, or a plant equally capable of edging your tree-lined rocky pathway and the swampy area by your pond, Mondo Grass fits the bill.

mondo grass guide

Mondo Grass Quick Overview

Botanical name (Family)Ophiopogon jabonicus (Liliaceae family)
Sun requirements Partial shade or dappled sun preferred
HardinessDepending on the variety, Zones 6-11
Water needsMinimal once established; tolerant of dry periods
ToxicityNon-toxic
InvasivenessConsidered safe in most areas (such as the Pacific Northwest), but can be invasive in warmer growing zones
Primary growth seasonSlow-growing evergreen; produces small white or light purple flowers in summer, and small blue fruits
Typical sizesDepends on variety, but most commonly one foot tall and wide.

Types of Mondo Grass

Ophiopogon Japonicus

photo of Ophiogogon Japanicus, a type of Mondo Grass

Ophiopogon Japonicus is the most common type of Mondo grass. It has an average height of 6 to 10 inches, but it can grow up to 12 inches tall and 15 inches wide per plant.

This type of Mondo Grass minimizes the time and effort you need to spend in maintaining that area of your yard in three ways.

  1. Its spreading habit helps keep your yard weed free.
  2. It is drought-resistant, making it a great option for those who don’t spend a lot of time watering their garden.
  3. It flourishes without full sun exposure, making it a great choice for under trees and other areas you don’t want to mow.

This variety of Mondo Grass is particularly resilient and can be grown in Zones 7-11.

Dwarf Mondo Grass (Ophiopogon japonicus ‘Nanus’ or ‘Gyoku-ryu’)

photo of a dwarf mondo grass

There are several cultivars of Dwarf Mondo Grass, including Nanus, Fuiri Goyoku, and Black Dragon. These varieties of Mondo Grass only grow to a fraction of the size of the other species in this family (just 1-6 inches, depending on the type). Dwarf Mondo Grass has slender leaves that give it a more delicate appearance, with cobalt blue fruits. It also has a mounding growth pattern.

Note: Since each plant has a much smaller width and shorter height than other types, and is slow-growing, you’ll need to plant Dwarf Mondo Grass seedlings more closely if you want to achieve a dense ground cover quickly.

Dwarf Mondo Grass appreciates dappled sunlight or partial shade, but can tolerate more sunlight (six hours plus) compared with some other Mondo Grasses. It can grow successfully both in well draining soil and in moist soil.

That versatility makes it great to grow in shady areas, rock gardens, around water features, or even in pots. Its short height makes Dwarf Mondo Grass perfect for planting between paving stones in a pathway.

Black Mondo Grass (Ophiopogon planiscapus ‘Nigrescens’)

photo of black mondo grass

Black Mondo Grass is a landscaping attention-getter. As its name implies, it is a darker shade than typical grass, black with reddish-brown or purple undertones. However, don’t be concerned if your new plants look greenish.

The leaves start out more of a green color and turn to its dark shade once it’s more established. When it self-propagates, some of the offsets can be green, so you may want to weed those out if they don’t turn black as they mature.

Black Mondo Grass grows in mounds that reach 8-12 inches high, and blooms in the summer months. While some types of Mondo Grass hide their flowers under their greenery, black Mondo Grass produces showy flower spikes held high above the foliage.

Black Mondo Grass has a slightly cooler preferred range than other Mondo Grass, specifically Zones 6-9. It flourishes in part shade (with no more than a few hours of direct sunlight daily).

It requires a bit more maintenance and patience than other types of Mondo Grass. Unlike some of the other Mondo Grasses, which are more drought-resilient, Black Mondo Grass prefers to be kept moist, so it needs to be watered routinely.

Silver Mist or Variegated Mondo Grass  (Ophiopogon japonicus ‘Kijimafukiduma’ or Ophiopogon jaburan ‘Variegatus’)

photo of ophiopogon japonicus, a variety of Mondo Grass
Supportstorm, Public domain, via Wikimedia Commons

Both Silver Mist and Variegated Mondo Grass are attractive cultivars with green and white variegated leaves. This bi-color effect adds a lot more visual interest than the plain green varieties.

The main difference between these types is the size. The leaves of Silver Mist are about ten inches, while Variegated Mondo Grass is quite tall, maxing out at 12-18 inches.

How To Grow And Propagate Mondo Grass

Ideal Mondo Grass Growing Conditions

variegated Mondo Grass in the garden

Mondo grass is an incredibly versatile plant that can be used for many different purposes in your landscape. It is in the same family as lilies and asparagus, with attractive foliage that is resilient in many different environments.

The perfect growing conditions for Mondo grass are usually the problem areas of your garden where first-choice plants fail. They prefer partial shade, tolerate rocky soil and steep slopes, can handle consistently moist roots as well as drought, and need little to no maintenance, so they’re perfect for inaccessible areas.

Here are just a few of the great options for how you can use Mondo Grass in your landscape:

  • Weed-Suppressing Ground Cover: When Mondo Grass is allowed to spread, it forms a dense ground cover and rhizome root-mass. This can be a great option for an area with lots of weeds that you’d like to crowd out. The density of the Mondo Grass roots can out-compete many common weeds once it is well-established.
  • Under Trees: Since Mondo Grass can cope well with shade and does not need to be mowed frequently, it makes an ideal turf to fill the shaded areas under trees.
  • Lining Paths: Because of its weed-suppressing quality, a row of Mondo Grass makes a great pathway-liner, and Dwarf Mondo Grass varieties can be used between stepping stones.
  • Coastal Landscapes: Mondo Grass is tolerant of substantial wind. It is also tolerant of the high levels of salt in the air near the coast.
  • Solidifying Slopes: The dense root mass of Mondo Grass is great for reducing erosion. It is a great ground cover for steep slopes because it doesn’t need to be mowed.
  • Bordering Water: Although Mondo Grass is fairly drought tolerant, it also grows well in very wet areas. You can encircle a pond in Mondo Grass, and it will grow alongside streams as well.
  • Acidic soils: Mondo Grass prefers a pH of 5-6.5. That makes them a great plant to grow under pine trees, where fallen needles have acidified the soil. They are good companion plants for other acid-soil loving plants like rhododendrons, blueberries, and succulents.

Watering Needs

Mondo Grass needs to be watered very consistently when it is young. For the first year after planting seed, you should keep the roots moist. After that first year, when your Mondo Grass is established, it will be much lower maintenance.

Established Mondo Grass appreciates watering, but will tolerate drought for longer than true grasses. Healthy leaves are typically a bright, rich green. 

Note: If the leaves lose their darkness or vibrancy, it’s a good sign they need more water. 

Propagating Mondo Grass

a hand putting Mondo Grass seeds to the soil

Mondo Grass is one of the easier plants to grow and propagate. You can grow your own by purchasing seeds, planting seedlings from your local plant store, or dividing existing clumps of Mondo Grass. The plant will self-propagate (spread on its own via rhizomes) once it is established.

Before planting, if the soil is compacted, you may want to work the area up using a rototiller. Mixing in roughly 2-3 inches of compost will produce the best results.

Info: Planting in slightly acidic soil is best for mondo grass. If your soil pH is higher than its preferred range (a pH of 5-6.5) you can amend it with sulfur, iron sulfate, peat moss, or pine needles.

Mondo Grass also grows well in containers.

Ideally you will want to plant your mondo grass in early spring following the last frost. It is possible to plant later in the season as long as you provide enough time for your plant to establish before frost sets in.

If planting in full sun be sure to water thoroughly following transplant, and for the first year after planting.

Fertilization Needs

It’s a good idea to amend your soil with compost or organic fertilizer before planting new Mondo Grass. Following the initial planting, use diluted organic fertilizer once every spring for the first few years after planting to keep your plant looking healthy.

Weed management

The most challenging aspect of propagating Mondo Grass is keeping weeds from overtaking the area you’re planting. Once it is established, the Mondo Grass should out-compete most weeds, but during propagation and when the plants are young,  there will be enough room between plants for weeds to come through. 

The best ways to handle this are hand-weeding and/or using straw or wood as mulch in the areas directly surrounding your plants after ridding the area of weeds (even small ones) by hand. 

Note: Mowing your Mondo Grass to 2-3 inches in the spring will encourage it to spread faster, so it will have more weed-suppressing capabilities in the second year.

We recommend that you avoid using herbicides on or near your Mondo Grass if possible. If you must use herbicide, read the label carefully and apply it minimally. Remember Mondo Grass is not really grass, so look for Mondo Grass specifically on the “compatible plants” part of the label.

Mondo Grass Maintenance

a person using a push reel lawn mower to maintain Mondo Grass

Mondo grass requires very little maintenance. For this reason, it is an ideal plant to grow in areas that are difficult to reach such as along steep slopes, flower beds and under trees.

To keep this plant looking its best, simply remove any weeds as they come up and water occasionally during dry warm weather.

In the springtime, you will want to mow Mondo Grass being used as turf down to 2-3 inches. Or if you have just a few ornamental plants you can  trim back any ragged leaves to help your plant looking its best using a set of grass shears.

We also recommend dividing the clumps of this plant every three or so years if they’re getting too dense.

Pests and Diseases

Mondo Grass is an incredibly resilient plant that is both tough and durable. It will stand up to everything from shade to deer. However, there are a few things to watch out for.

  • Slugs: Mondo Grass can attract slugs, which may disfigure the plants.
  • Weeds: Weed the ground thoroughly before planting Mondo Grass, then either hand-weed or use mulch around small plants until they establish and fill in the gaps. If necessary, some herbicides can be used to suppress weeds around Mondo Grass, but avoid these when possible, and make sure the label specifies that it is safe to use on Mondo Grass specifically.
  • Dull, pale color: When Mondo Grass loses its deep vibrant green color, it’s a good warning sign that it isn’t getting enough water.
  • Spreading to unwanted areas: Rhizomatic plants are a double-edged sword. They’re a great tool when you want a plant that will spread to fill an area, but it can be frustrating when they spread beyond the areas you wanted. This is more of a problem in the warmest climates, where Mondo Grass can be invasive. If you live in a growing zone where Mondo Grass spreads easily, make sure to contain it with a barrier buried deep enough to block the underground runners. In a worst-case scenario, you can use a herbicide with a label that specifies it will kill Mondo Grass.

Fill Your Landscaping Trouble Areas with Mondo Grass

Mondo Grass isn’t actual grass, but when it comes to maintenance it is, in many ways, better than true grasses.

Once established, it requires minimal maintenance (occasional watering, and mowing and fertilizing just once each spring). It is resilient in a wide variety of growing environments and suitable for countless different landscaping applications, particularly spots where other plants won’t grow.

If you live in the right growing zones, there is almost certainly a difficult-to-fill area of your landscape where Mondo Grass would be a perfect fit.

Photo of author
Author
Emily Cordo
Emily Cordo is a Master Gardener, writer, photographer, and artist. She is passionate about regenerative agriculture and landscaping, and about integrating art into those environments.

31 thoughts on “The Complete Guide To Mondo Grass – How To Grow and Care For”

  1. My Mondo grass is dying I don’t know why, it has enough water, planted in shaded area just over a year old, it has river sand at the bottom then potting soil

    Reply
  2. My border of flower bed mondo grass has gradually expanded into about 2 feet of the surrounding lawn. It is thick, carpet like and looks great. I’m wondering if I need to just let it keep growing and cover the entire lawn. Suggestions?

    Reply
  3. My yard guys mowed and weed eated all my dwarf mondo. It looks terrible now. Will it grow back or do I need to replace it? It is just July 15th

    Reply
  4. Will Mondo grass tolerate very wet soil and occasionally being under water? I am looking for something to plant near a tidal river. Thank you!

    Reply
  5. Hi,I am living in a tropical region..even though the watering is normal m to this plant,it shows a type of fungal infections like decaying the roots and leaves turns to yellow and leads death of the plant..what may be the possible solution for this..

    Reply
  6. I want to use Mondo grass as a border around my paved patio. But, it does snow occasionally and does get below freezing. If mondo grass is not applicable might you have some suggestions. I would like something which covers, is green and spreads but doesn’t get too unruly. Thanks.

    Reply
  7. I’m thinking of planting Black Mondo grass under some native shrubs as a feature along the driveway and in a full sun position.
    What are your thoughts?
    What kind of fertilizer can I use and how often?

    Thanks
    Dominic

    Reply
    • Hi Dominic, that should work well. Fertilizing isnt really needed, but you can use a slow release fertilizer during the spring and summer – probably apply once each in these seasons.

      Reply
  8. We use Mondo grass for the turf of our Memorial Garden here at our retirement community. The ashes that are scattered have evidently have raised the pH to about 7.0. I understand the best pH for Mondo grass is 5.0 to 6.5. Should we apply some material to lower the pH? If so what would you suggest? Thanks so much!

    Reply
    • Hi Stanley,
      I wouldn’t stress too much about those levels, but if it goes much higher it could be a concern.
      You could either go the long way – by adding some compost or an acidic mulch. Or if you want do it it faster then you can add some aluminum sulfate (available on Amazon here).

      Reply
    • It is prone to other grasses growing through it – so it is probably just that. You can pull them out by the roots and hopefully, they don’t come back.

      Reply
    • NO!! Leave alone-it is sprouting it’s flowers!! Look at some liriope images to see what is going to happen! Little pale lavender or white “balls”.

      Reply
    • Yes it can be grown in a container – in fact it loves it! With regards to the size, it really doesn’t matter and it depends on what else you plan to plant with it.

      Reply

Leave a Comment