How to Grow Sedge Black Mondo
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Sedge Black Mondo
Ophiopogon planiscapus 'Nigrescens'
grassBlack Mondo Grass is a dramatic evergreen ornamental grass with nearly black, narrow foliage that forms dense, cascading clumps. It's a slow-growing, low-maintenance ground cover or accent plant prized for its striking dark color and fine texture. Despite its common name reference to sedge, it's actually a member of the Asparagaceae family.
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Example Sedge Black Mondo timeline · Pittsburgh, PA (Zone 6b)
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Plant Sedge Black Mondo
Around Apr 17Near Pittsburgh's average last spring frost.
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Tend & protect
Late spring–summerWatering, feeding, and pest-watch reminders.
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Harvest Sedge Black Mondo
Around Oct 14≈ 180 days after planting
Sample dates for Pittsburgh, PA. Sign up to get exact Sedge Black Mondo dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Thrives in zones 5b-10b; best performance in zones 6-9
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Get my Sedge Black Mondo timeline →Growth Stages
Establishment
3-6 monthsYoung plants are small with sparse foliage; growth is very slow
Water regularly; avoid disturbance; mulch around base to retain moisture; be patient as growth is gradual
Vegetative Growth
6-18 monthsFoliage gradually expands with arching leaves becoming darker and denser; clumps slowly widen
Maintain consistent moisture; light fertilization in spring with balanced fertilizer; remove any brown or damaged leaves
Flowering
2-3 weeks in late summerProduces delicate, small purple-white flowers on thin stems above the foliage; flowers appear in late summer
Flowers are non-showy; leave for interest or remove to focus energy on foliage; flowers may be followed by black berries
Winter Dormancy
3-4 monthsFoliage remains evergreen; color intensifies slightly; growth slows significantly
Minimal watering; no fertilizer; do not cut back foliage; protect from extreme cold below -10°F in exposed locations
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
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Remove manually; use copper tape around containers; apply neem oil or diatomaceous earth; encourage predators like beetles
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Increase humidity with misting; spray with insecticidal soap; use neem oil; rinse foliage regularly
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Improve air circulation; reduce overhead watering; remove affected foliage; apply fungicide if severe; ensure well-draining soil
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Allow soil to dry between waterings; ensure excellent drainage; repot if in containers with fresh soil; remove affected tissue
Uses
Ornamental Ground Cover & Accent
HouseholdBlack Mondo Grass creates stunning visual contrast in shade gardens as a ground cover, border edging, or specimen accent plant. Its nearly black foliage provides dramatic background for lighter-colored plants. [source]
Container & Landscape Design
HouseholdExcellent in containers, raised beds, and Japanese-style gardens where its fine texture and dark color enhance modern and traditional designs. Works well massed as edging or scattered as focal points. [source]
Wildlife Habitat
WildlifeProvides shelter and cover for ground-dwelling insects, small lizards, and beneficial creatures. Flowers attract pollinators and foliage offers protection. [source]
Dried Arrangements
CraftThe delicate flower spikes and structural foliage can be dried and used in floral arrangements and craft projects for textural interest. [source]
Harvest Tips
Not harvested for food or cutting; simply maintain by removing dead foliage and dividing every 3-4 years. Divide in spring by carefully separating clumps and replanting at same depth.
Fun Facts
- 🌱 Despite its common name 'sedge,' Black Mondo Grass is not actually a sedge or true grass, but a member of the lily family (Asparagaceae), making it more closely related to asparagus than to ornamental grasses.
- 🌱 The cultivar name 'Nigrescens' literally means 'becoming black,' referring to the gradual darkening of foliage as the plant matures—new growth may be slightly greener before darkening to deep black-purple.
- 🌱 Black Mondo Grass is extremely slow-growing and long-lived, often taking 2-3 years to reach mature size but then requiring minimal maintenance for decades in ideal conditions.
Gardening Terms
New to gardening? Learn about terms used in this guide:
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