Mondo grass

Ophiopogon japonicus

In other languages: Slangenbaard (Nederlands) · Herbe aux turquoises (Français)

Mondo grass comes from Japan, Korea and China and is an evergreen, grass-like perennial about 20 cm tall. It forms dense tufts of narrow, dark green, arching leaves that stay attractive all year. In July and August small pale lilac or white flowers appear among the leaves in short sprays, followed in autumn by glossy blue berries. It spreads slowly by runners and is an excellent ground cover for partial shade and shade. The compact cultivar ‘Kyoto Dwarf’ stays even lower. Not to be confused with black mondo grass (Ophiopogon planiscapus ‘Nigrescens’).

Updated on 9 October 2026

Light
Partial shade or shade
tolerates little sun
Moisture
Normal
no wet feet
Legal basis
Sand or loam
acid to neutral
Hardiness
down to -15 °C
protect young plants
Size
0.2 m
tall, 0.3 m wide
Flowering
July–August

Key facts
Pruning months	March
Height	0.2 m
Native to Belgium	No, planted
Poisonous to people and pets	Not known to be poisonous
Flowering	July–August

Identify

Mondo grass: how do you recognise it?

Habit: Dense, grass-like tufts 15–25 cm tall and 30 cm wide, slowly spreading by runners.
Foliage: Narrow, strap-like, 2–3 mm wide, dark green and glossy, arching; green all year.
Flower: Small bell-shaped flowers in short sprays, partly hidden among the leaves, in July and August.
Colour: Pale lilac to white; later glossy blue berries.
Roots: Fine roots with small tubers and runners by which the plant slowly spreads.

Flowering: July–August · Plants: April–May and September · Pruning: March

In your garden

Why grow it?

Evergreen: a fresh green lawn of foliage all year, even in winter.
Works as ground cover in partial shade and shade, where grass and other plants struggle.
Glossy blue berries in autumn, beneath the foliage.
No mowing: little upkeep and very tough.
Gives path and border edges a crisp, neat line without needing to mow a lawn.

Mondo grass: where does it grow best?

Partial shade to shade; in full sun the foliage scorches and turns yellowish.
Humus-rich, well-drained sandy or loamy soil, acid to neutral.
Moderately moist: the soil must not dry out, nor stay wet.
Plant 15–20 cm apart for a quickly closing carpet, or 25–30 cm if you are patient.

Light: Partial shade and shade
Soil type: Sand or loam
Acidity: Acid or neutral
Moisture: Normal
Size: 0.2 m tall, 0.3 m wide
Hardiness: Hardy (to -15 °C)

Goes well with

Hosta: Broad leaves above the narrow, glossy ribbons.
Ferns: Fresh green foliage in the same partial shade.
Japanese maple: Delicate foliage above the low green carpet.
Azalea: An evergreen carpet under the flowering shrub, on the same acid soil.

Maintenance

Mondo grass: when and how to plant it?

Plant in April–May and September.

Plant in April–May or in September, when the soil is not frozen or too wet.
Loosen the soil and mix in leaf mould or potting compost to make it humus-rich and free-draining.
Set the plant at the same depth as in its pot, with the crown at soil level, and firm the soil.
Keep 15–20 cm between plants for quick closing.
Water in generously at once and lay a thin layer of leaf mould around the plants, without covering the crown.

Care

Water: In the first year, water regularly in dry weather; later only in dry summers.
Feeding: A thin layer of compost or organic fertiliser in spring is enough.
Mulching: A thin layer of leaf mould in autumn keeps the soil moist and protects the roots from frost.
Weeding: In the first year, until the carpet has closed, weed regularly.
Tidying: Remove leaf litter from the tufts and cut off browned leaves in March.

Tip: Use it as an evergreen ground cover in partial shade and shade and protect it in hard winters with a layer of leaves. Cut off damaged leaves in March.

Mondo grass: when to prune it?

Pruning months: March.

When: In March, before the new shoots appear.

How:

Cut leaves browned by frost or drought to 5 cm above the ground.
A very old or tired carpet can be mown high or cut back in March; it regrows.
Remove dead pieces from the tufts.

Pruning: when and how · Pruning calendar and basic rules

Propagation

Division: In April–May: lift the clump, divide it into pieces with roots and replant at once 15–20 cm apart. It is easy.
Seed: Sow fresh seed in autumn or spring in a cold frame; it germinates slowly and it takes years for the plant to close up.

Mondo grass: how does it get through the winter?

Hardy to −15 °C: protect young plants.

Hardy down to about −15 °C; in a sheltered spot in Flanders usually without problems.
Protect it in hard frost with a layer of leaves or horticultural fleece, especially young plants.
In a pot: put it against a wall or wrap the pot in hessian, because the roots freeze faster than in the open ground.

Diseases and pests

Slugs: Nibbled leaves or holes in young shoots. Collect them in the evening or lay a ring of coarse grit around the plant.
Frost damage: Brown tips or leaves after a hard winter. Cut them off in March; the plant regrows by itself.
Root rot: Yellow, limp leaves where water stands. Improve drainage with coarse sand or move it.
Weeds: In the early years weeds grow between the tufts. Weed regularly until the carpet has closed.

Through the year

March: Cut off browned leaves. Add compost.
April: Plant or divide.
May: Plant. Mulch. Weed.
June: Water in dry weather. Weed.
July: Flowering starts. Water in dry weather.
August: Flowering. Water in dry weather.
September: Plant. Blue berries appear.
October: Lay leaves as mulch around the plants.
November: Protect young plants against hard frost.

You and this species

Did you know?

The name Ophiopogon comes from Greek: ophis means snake and pogon beard; hence ‘snake’s beard’.
It is not a true grass: it belongs to the asparagus family, like hyacinth and asparagus.
In Japan it is called ‘ryūnohige’, which means dragon’s beard.

Garden plants · All species