Ophiopogon Japonicus Plant Care

For a ground cover that is low maintenance, it helps to look at the mondo grass traditionally grown in Japanese gardens. The grass stays small and works well for courtyards, entry gardens, and atriums. It also works well as an edging plant for your water garden, or you can arrange it around a fountain.

What Is Ophiopogon Japonicus?

The Ophiopogon japonicus is an evergreen perennial known as mondo grass, a relative of the lily cherished in Japanese garden arrangements.

The grass is native to Korean and Japanese woodlands featuring clumps of stemless leaves that are dark green and grow tuberous roots.

When mondo grass grows, the flower color varies, allowing for a variance in contemporary gardens when you plant them strategically.

They make for exceptional ground cover in part shade and are available in numerous cultivars like the Silver Mist with variegated white-striped leaves and the Albus with white flowers.

You also get a dwarf mondo grass called the nana that grows half the size of the parent plant.

Ophiopogon Japonicus Care

mondo grass

The mondo grass is a hardy plant that grows in different weather conditions. All it needs is water, and it’s resilient to deer. You can grow the outdoor plant in partial shade, but the roots spread fast and thrive all year round.

The fact is that this grass is every gardener’s dream as it needs little maintenance and is ideal for growing in hard-to-reach areas of your landscaping, like slopes. The best places to grow mondo grass are USDA zones 7 to 12.

Perfect Soil Mix and Transplanting

Dwarf mondo grass thrives best in rich, well-drained soil that is slightly humusy and acidic. Appropriate soil for planting the grass is loamy or sandy.

The best part is you can transplant them by removing an entire clump or divide the clumps for mass planting into smaller sections, as each division can have up to eight leaves with multiple rhizomes.

You can plant them up to 12 feet apart and cover them with a layer of soil, and water them until moist.

Light Exposure

mondo grass light exposure

Growing mondo grass is very little maintenance and flourishes in full to part shade, but they can also tolerate full sun. When exposed to temperatures of 0°F to 10° F(-18° to -12° C) for short periods, they remain hardy.

Mondo Grass Grows With Weekly Watering

You can water mondo grass weekly and in extreme heat or grow in containers. They do need added water. The grass prefers well-drained soil, and the ground needs to remain moist. If submerged for a short period, they can also survive.

mondo grass watering

You can apply a slow-release fertilizer during spring and summer to provide the grass with the nutrients it needs during the growing season.

Alternatively, you can add a thin layer of compost annually for added nutrients.

Grooming Dwarf Mondo Grass

It has a grass-like nature, but it still provides you with low maintenance. Still, the shoots and roots take over your garden fast if you do not trim them back. You can restrict the spreading in shady areas using submerged planters.

Propagating Ophiopogon Japonicus

Propagating mondo grass is accessible by visiting a local nursery to buy seeds or grow them from starter plants with a root system. To prevent weeds from taking over the grass, you can add mulch around the plants, which helps block sunlight.

The best time to plant the grass is in early spring, after the frost finishes. After that, you can plant the grass into the growing season, provided it has enough time to establish a root system. The grass also needs to grow about four to six inches apart.

If you already have mondo grass growing, the easiest method to propagate them is through division during spring. You can separate the new plants by clipping off the side shoots to transplant in a new spot.

Use a cold frame with sandy compost to germinate the seeds. Once the plants are large enough, you can move each seedling into a container to grow through winter.

Then in spring, move them to a permanent location where they will flourish and grow.

Ophiopogon Japonicus Varieties

You can find three mondo grass types available to grow in your garden.

Black Mondo Grass

black mondo grass

The black mondo grass is ideal for growing for an aesthetic appeal in the garden, welcoming guests. It has a darker hue than your typical light-green colors seen in most lawns. In addition, it is slow-growing and branches out with stolons underneath the surface.

The mondo grass does well in sunny spots but can grow in shady yards. In warm periods, the plant type needs frequent waterings to maintain growth. You can add it to flowerbeds and grow up to ten inches tall during the summer months.

The leaves start light green turning black in the growing season, and they are cold hardy to last through winter.

Dwarf Mondo Grass

dwarf mondo grass

The grass grows to four inches tall with slender leaves and has a petite look for ground cover in flowerbeds. The grass is cold resistant and pest resistant.

Ophiopogon Japonicus Diseases and Pests

In most garden parts, the mondo grass is hardy, drought, and salt tolerant. The biggest problem you might face with the grass is slugs. You can grow it around black walnut. It is rabbit and deer resistant. But if you live in USDA zone 6a, you need to provide the plants with shelter against the cold winter temperatures.

Frequently Asked Questions

Yes, you can divide mondo grass with the following steps:

  1. If grown in a pot, then remove it from the container. For garden growing, use your garden fork to raise the plant.

  2. Start working on the roots to loosen them up. You may need to use a knife or shover to cut them.

  3. Separate each piece into several plants by choosing strong and healthy roots.

  4. Plant in separate pots or on the ground at eight-inch intervals.

If your mondo grass turns yellow, it is a sign of root rot, or you will see leaf tip burn from yellow to brownish color. To treat the problem, you will need to use a fungicide.

A standard mongo grass can spread up to one foot within two years. At the same time, dwarf mondo grass can take up to three years to reach a spread of four inches.

You can buy mongo grass at a local garden center or online in the form of seeds or plantlets. The good news is that you can buy the grass here at Plantly and have it delivered to your door.

Whether you want to buy, sell or simply reach out to other plant enthusiasts, Plantly is the right place to be!

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