Black Mondo Grass and Lilyturf: Monkey-Grass Madness

Strikingly-Dark Ground Cover

Black monkey grass can create contrast in a landscape design as this photo shows.
Black mondo grass is as truly black as a plant can be. David Beaulieu

Before describing black mondo grass and giving information about its care, some explanation is needed regarding the names of this and similar plants, such as lilyturf. "Monkey grass" is a name that you'll hear in this context, a fact that can confuse folks as to precisely what plant we're talking about. That's why serious-minded types are apt to consider the use of the common names of plants (compared to the more reliable scientific names of plants) as mere monkeying around, at best, and as sheer madness, at worst.

"Monkey grass" is a name you are more likely to hear in the Southern U.S. than elsewhere. But to what plant, specifically, does it refer? Unfortunately, the term is commonly applied to two entirely different plant groups:

  1. Ophiopogon (the group to which black mondo grass belongs).
  2. Liriope (which is the "lilyturf" mentioned above).

While they look somewhat similar and are used in similar ways in landscaping, these perennials are, in fact, two totally different plants. But because these two East Asian natives do look a bit alike, people have become lax in referring to them by common name, with the result that "mondo grass" and "monkey grass" are used for both. Sticklers may make the distinction that "mondo grass" refers to Ophiopogon, while "monkey grass" refers to Liriope, but, in reality, these names are used interchangeably. But enough about the confusion surrounding these two plants. Let's get to a description of the featured plant in this article: black mondo grass.

Black Mondo Grass: Traits, Care, Uses in Landscaping

Black mondo grass (Ophiopogon planiscapus 'Nigrescens'), like Liriope, looks very much like an ornamental grass. But for all their grassy looks, neither of these perennials is a member of the Poaceae family (that is, the true grasses). In fact, both belong to the Ruscaceae family.


What strikes one immediately about black mondo grass is that the adjective in its name is no exaggeration. This fact is refreshing, since many of the so-called "black plants" are little more than deep purple specimens. So if you're a lover of Gothic landscaping, you may experience a bout of monkey-grass madness when you first set eyes on this beauty.

Black mondo grass may also produce pinkish-lavender flowers, which are followed by purplish-black berries. So, technically, it's a flowering ground cover. But, for most people, all of this takes a back seat to the unusual evergreen to semi-evergreen foliage. It grows to be 6 inches tall and has a clumping habit.

Many list black mondo grass for planting zones 6-9. However, the label that some plants come with list it as zone-5 hardy. Many zone-5 gardeners can attest to its ability to survive there. Apply mulch in order to give it winter protection if in doubt. As time goes by, your plant may even produce off-shoots.

It's a slow grower. Divide it in spring. In early spring, trim off any leaves that have become ratty-looking over the winter, before the new growth comes. More severe spring haircuts may be called for when trimming older plants.

Another tricky issue for beginners with black mondo grass is its sunshine needs. You'll see some experts list it as a sun plant, and others as a shade plant. So what gives? Are the experts monkeying around with you? No. Southerners should treat it as a shade plant, because intense sunlight in warm climates will fade its trademark color. Northerners, meanwhile, can grow it in full sun.

But regardless of where you live, the claim that it is "shade tolerant" is justified. It prefers fertile, evenly-moist, well-drained soil but will tolerate some drought once mature. Those in deer country can add it to their list of deer-resistant ornamental grasses with which to keep Bambi at bay.

Black mondo grass makes for a good edging plant. If you have anything at all of a designer's eye, the dark color of the plant's leaves will bring out the artist in you.

Design possibilities are endless, but you may especially enjoy creating contrasts by placing black mondo grass next to plants that sport bright colors. For example, if you grow yours in full sun, partner it with 'Angelina' sedum for contrast. Scotch moss (Sagina subulata 'Aurea') would also work here.

If you grow black mondo grass in partial shade, try pairing it with a bicolored hosta. In this case, you'll have another contrast, as well: namely, in terms of plant texture. Black mondo grass has a fine texture, while hosta's is coarse.

Black Mondo Grass Not the Only Type of Ophiopogon

A plant in the same genus as black mondo grass and just as shade-tolerant is Ophiopogon japonicus (zones 6-9). It can reach 6-10 inches in height, although dwarf types also exist (for example, the 'Kyoto Dwarf' stands 2-4 inches tall). Not as showy as black mondo grass, this plant makes up for it by being useful as a ground cover.

O. japonicus will spread, which is a double-edged sword. Its ability to spread can make this less showy monkey grass invasive. But its ability to spread enables you to grow it as an alternative to lawn grass. As such, it can be used to form a shade-tolerant "lawn." Lovers of low-maintenance landscaping, take note: This is a lawn that you'll never have to mow.

Its tendency to spread allows it to serve other purposes, as well. Plant it between the cracks of garden stepping stones, for example (some use creeping thyme for this purpose). Such plants that spread via underground rhizomes also tend to be good for soil erosion control. Finally, many homeowners struggle with the problem of how to plant under trees, and tough plants such as O. japonicus often provide a long-sought solution.

The Other "Monkey Grass"

Let's summon that other "monkey grass" again, not Ophiopogon, but its look-alike, lilyturf (Liriope). Two types are:

  1. Liriope spicata
  2. Liriope muscari

Liriope muscari offers more ornamental value and is popular in the South, but it isn't as hardy as Liriope spicata (suited to USDA planting zones 4-10).

One advantage that Liriope spicata has over black mondo grass is that its flowers are showier, because the flower stalks rise further above the foliage than on black mondo grass. The latter's flowers are sometimes hidden by the foliage. Some types of Liriope also boast variegated leaves.

Lilyturf is used in the same way as Ophiopogon: for edging, etc. In fact, its use as an edging plant led to the nickname, "border grass." Like O. japonicus, it spreads. Being the faster grower of the two "monkey grasses," its potential for invasiveness is greater.

What's in a Name?

Ophiopogon is made up of two Greek words, ophis (meaning "snake") and pogon (meaning "beard"). In fact, to bring yet another common name into the mix, this perennial is sometimes called "snakebeard." The reference is thought to be to the floral spike.

Liriope comes from the name of the mother of Narcissus in Greek mythology. The muscari species was so named because its blooms look somewhat like those on grape hyacinth (Muscari botryoides). The name of the spicata species references the flower spike.

Speaking of names, let's conclude by coming back to the problem mentioned at the start of this article: the "monkey-grass madness," if you will, of jumbled up common-name usage for Ophiopogon and Liriope.

Paul R. Fantz conducted a study that sheds some light on just how much confusion reigns in this issue. Based upon his study of eight species of Ophiopogon currently available in the industry trade, Fantz notes that these plants are often incorrectly marketed as being "Liriope." So if it's O. planiscapus 'Nigrescens' that you're seeking, be sure to go to the garden center in person and look for its black grass blades. Trust your eyes, not the name used. This is one sure way to beat the confusion.