How to Grow Japanese Mondo Grass

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Japanese Mondo Grass

Ophiopogon japonicus

grass

Japanese mondo grass is a low-growing, evergreen groundcover with dark green, grass-like foliage that forms dense clumps. It produces delicate pale purple or white flowers followed by ornamental blue-black berries. This hardy, shade-tolerant plant is popular for landscaping, edging, and underplanting in woodland gardens.

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Example Japanese Mondo Grass timeline · Pittsburgh, PA (Zone 6b)

  1. Plant Japanese Mondo Grass

    Around Apr 17

    Near Pittsburgh's average last spring frost.

  2. Tend & protect

    Late spring–summer

    Watering, feeding, and pest-watch reminders.

  3. Harvest Japanese Mondo Grass

    Around Apr 18

    ≈ 1 days after planting

Sample dates for Pittsburgh, PA. Sign up to get exact Japanese Mondo Grass dates for your own zip code.

Growing Conditions

☀️
Sun: Partial shade to full shade preferred; tolerates full sun in cooler climates but may bleach in intense heat
💧
Water: Moderate moisture; keep soil consistently moist but not waterlogged. Drought-tolerant once established, but performs better with regular watering during growing season
📏
Spacing: 6-12 inches
📅
Days to maturity: Not applicable (ornamental groundcover; establishes in 1-2 seasons)
🌱
Planting depth: Shallow planting; crown should be at or slightly above soil surface

Soil

Type: Well-draining loamy or sandy soil
pH: 6.0-7.0
Amendments:
Organic compost Peat moss for moisture retention Perlite for drainage

Growing Zones

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Thrives in zones 5-10, most vigorous in zones 6-9

5a 5b 6a 6b 7a 7b 8a 8b 9a 9b 10a 10b

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Growth Stages

1

Establishment

4-8 weeks

New plants are small clumps with limited foliage. Root system is developing

Keep soil consistently moist to encourage rooting. Protect from extreme heat and cold. Mulch lightly to retain moisture

2

Vegetative Growth

6-12 months

Clumps expand outward, producing more grass-like leaves. Plant fills in the space gradually

Water regularly during dry periods. Apply balanced fertilizer in spring. Remove any dead foliage

3

Flowering

4-6 weeks (mid-summer to early fall)

Small delicate flowers appear on short spikes, typically pale purple, white, or lilac in color

Flowers are inconspicuous but attractive. No special care needed; allow flowering to occur naturally

4

Fruiting & Maturity

4-8 weeks

Small, ornamental blue-black berries develop after flowering. Plant is fully mature and dense

Berries persist into winter and are attractive to wildlife. Established plants are very low-maintenance

Companion Planting

Plan your garden →

Plant with:

Avoid planting near:

Aggressive spreaders like mint Plants requiring full sun and dry conditions

Common Pests

  • Increase humidity, spray with water, apply neem oil if severe

  • Remove by hand, apply horticultural oil in dormant season

  • and

    Handpick, use slug baits, or create barriers with copper tape or diatomaceous earth

  • Improve drainage, reduce watering frequency, remove affected plants

Uses

🏠

Ornamental Groundcover

Household

Ideal for creating dense, low-maintenance groundcover in shade areas, garden borders, and between stepping stones. Its fine texture and evergreen nature provide year-round visual interest and erosion control on slopes. [source]

🦋

Wildlife Support

Wildlife

The ornamental blue-black berries attract birds and other wildlife in fall and winter. Dense clumps provide shelter and nesting habitat for small creatures. [source]

💊

Traditional Asian Medicine

Medicinal

In traditional Chinese medicine, Ophiopogon japonicus (called '麦冬' or mai dong) is used to moisten the lungs and nourish the yin. It is employed in herbal remedies for dry cough and respiratory conditions. [source]

🏠

Shade Garden Design

Household

Perfect for filling shady corners, under trees, and in woodland gardens where grass struggles to grow. Its compact growth habit makes it ideal for small spaces and containers. [source]

This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.

Harvest Tips

Not typically harvested; grown as ornamental. Berries are ornamental only and should be left on plant for wildlife. Division for propagation can occur in spring or fall

Fun Facts

  • 🌱 Japanese mondo grass is not actually a true grass, despite its common name—it belongs to the Asparagaceae family (related to asparagus and lilies)
  • 🌱 The ornamental blue-black berries persist through winter and are actually quite attractive to birds, who help disperse seeds naturally
  • 🌱 There is a dwarf cultivar called 'Nanus' that grows only 2-3 inches tall, making it perfect for small spaces and between pavers

Gardening Terms

New to gardening? Learn about terms used in this guide:

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