These Colorful Companion Plants Look Perfect Next To Black Mondo Grass

Black mondo grass (Ophiopogon planiscapus 'Nigrescens') is a purple-black groundcover that is worth its slow grow, as it provides gorgeous color in the garden. The strappy, glossy leaves are a deep blackish color that won't lose its color all season, being a sort of "evergreen" with deep, unusual hues for winter interest. While some clumping grass groundcover plants can be somewhat invasive in the garden, black mondo grass is not a problem in this regard — as long as you aren't planting the similar-looking mondo grass Ophiopogon japonicus, which can be invasive in southern states. To accent this beauty, consider companion plants to complement its coloring.

One option that would make a good companion plant for this perennial grass is the hellebore, (Helleborus spp.) which flowers in early spring — sometimes while there is still snow to be seen. Hellebores, which bloom as early as late December, produce flowers in a range of colors and their evergreen foliage starts perking up in late winter. The green-blue leave of Majorcan hellebore (Helleborus lividus) would look especially vivid next to black mondo grass.

Because black mondo grass spreads slowly, you can plant the hellebores fairly close by. Both of these clumping perennials can be easily divided if they get too big. In addition to a Majorcan hellebore, planting black-flowering or pink-flowering hellebores near your black mondo grass could create a striking display. Black hellebore cultivars include 'Wedding Party', 'New York Night', or 'Arthur's Black Buttercup'. Pink hellebore varieties are 'Pink Frost', 'Royal Heritage', or 'Paris in Pink'. Keep in mind that hellebore is highly toxic to humans when ingested.

You can also consider planting your black mondo grass near colorful heuchera plants, also known as coral bells or alumroot. This hardy, shapely foliage plant provides wonderful contrast to the slender blades of black mondo grass, and is one of the most colorful plants to grow in your garden that isn't a flower. Heuchera appears in spring with small clusters of leaves showing veined patterns with scalloped edges. These flowers produce delicate tall stems of tiny foamy flowers in late spring that last several weeks, in shades from white to red. 

As summer arrives, heuchera leaves increase in size and put on a wonderful foliage show. These plants come in a very wide range of cultivars, many of which have very striking foliage to create great color palettes in the garden, often shifting as the season progresses. As a companion to black mondo grass, there are some very dramatic color contrast possibilities for heuchera, including chartreuse, burgundy, bronze, orange, and red.

Red, bronze, and orange leaved varieties lend a bold look, such as the red and pink-toned 'Georgia Peach', or the vivid orange-peach shades of 'Sweet Tea'  which is a heucherella — a cross between heuchera and tiarella for a more shade-tolerant plant. There are purple-leaved heucheras to continue the dark violet theme of the black mondo grass, like burgundy-tinged 'Palace Purple', or the gorgeous deep violet 'Forever Purple'.  For a natural look and attractive contrast try 'Dale's Strain' with frosty green leaves accented with deep purple veins, or 'Dolce Spearmint', a silvery pale green variety with lovely pink flowers.