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Wire Grass Juncus tenuis

Other Common Name(s):

Other plants called Wire Grass:

Phonetic Spelling
JUN-kus TEN-yoo-iss
Description

Wire Grass is a perennial. flowering grass or sedge that does well in cold climates and wet heavy clay or loamy soil.  It is typically found in thickets and swamps and weedy locations like roadsides, sidewalks and parking strips. It has tough, but smooth, stems, medium green leaves that turn brown with frost, and tiny flowers clustered at or near the stem tips. Wire Grass can spread quickly with windblown seeds or rhizomes and can become weedy, although these same traits make it useful as a ground cover. Alternatively, it can be grown in a container. The genus name means rush. The species name means slender or thin,  referring to the leaves.

Wire Grass grows easily in average, medium to wet, soil in full sun or partial shade. Because the plant thrives in water, plant them along pond margins, in rain or rock gardens or in containers. Clumps of Wire Grass can easily be divided in spring and replanted. Wire Grass is undemanding and low maintenance, self-sowing with soft, touchable foliage. It should be mowed high (3 to 8 inches) to maintain a uniform look.

Insects, Diseases, and Other Plant Problems: 

No significant problems though some consider this plant weedy. Aphids can be a problem.

See this plant in the following landscape:
Cultivars / Varieties:
  • 'Blue Arrows'
    Blue green leaves
  • 'Blue Dart'
'Blue Arrows', 'Blue Dart'
Tags:
#water garden#sedge#low maintenance#erosion control#pond margins#NC native#thickets#swamps#groundcover#rock garden#naturalized area#native ornamental grass#wet soils tolerant#clay soils tolerant#rushes#container plant#weed#perennial grass#collier preserve tn
 
Cultivars / Varieties:
  • 'Blue Arrows'
    Blue green leaves
  • 'Blue Dart'
'Blue Arrows', 'Blue Dart'
Tags:
#water garden#sedge#low maintenance#erosion control#pond margins#NC native#thickets#swamps#groundcover#rock garden#naturalized area#native ornamental grass#wet soils tolerant#clay soils tolerant#rushes#container plant#weed#perennial grass#collier preserve tn
  • Attributes:
    Genus:
    Juncus
    Species:
    tenius
    Family:
    Juncaceae
    Life Cycle:
    Perennial
    Recommended Propagation Strategy:
    Division
    Seed
    Country Or Region Of Origin:
    North America, Alaska to Quebec, south to Texas.
    Distribution:
    Introduced world-wide (Europe, East Asia, Australia)
    Dimensions:
    Height: 0 ft. 6 in. - 2 ft. 0 in.
    Width: 0 ft. 6 in. - 2 ft. 0 in.
  • Whole Plant Traits:
    Plant Type:
    Ground Cover
    Native Plant
    Ornamental Grasses and Sedges
    Perennial
    Weed
    Habit/Form:
    Ascending
    Clumping
    Erect
    Growth Rate:
    Rapid
    Maintenance:
    Low
    Texture:
    Fine
  • Cultural Conditions:
    Light:
    Full sun (6 or more hours of direct sunlight a day)
    Partial Shade (Direct sunlight only part of the day, 2-6 hours)
    Soil Texture:
    Clay
    Loam (Silt)
    Soil pH:
    Acid (<6.0)
    Alkaline (>8.0)
    Neutral (6.0-8.0)
    Soil Drainage:
    Good Drainage
    Moist
    Occasional Flooding
    Occasionally Wet
    Available Space To Plant:
    12 inches-3 feet
    NC Region:
    Coastal
    Mountains
    Piedmont
    USDA Plant Hardiness Zone:
    2a, 2b, 3a, 3b, 4a, 4b, 5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b
  • Fruit:
    Display/Harvest Time:
    Fall
    Fruit Type:
    Capsule
    Fruit Length:
    < 1 inch
    Fruit Description:
    The seed capsule of each flower is ovoid with a small point at its apex. Each capsule eventually splits apart into 3 segments to release its tiny dust-like seeds.
  • Flowers:
    Flower Color:
    Green
    Flower Inflorescence:
    Cyme
    Insignificant
    Umbel
    Flower Value To Gardener:
    Showy
    Flower Bloom Time:
    Summer
    Flower Petals:
    Bracts
    Flower Description:
    Insignificant green flowers, clustered at the stem tips, appear May to September. With the first frost they turn brown. Each stem terminates in a branching inflorescence that has one or more umbel-like clusters of up to 10 flowers. At the base of this inflorescence, there are about 3 slender leafy bracts up to 4 inches long that form a V-shape. The petals and sepals are nearly identical in appearance and lanceolate in shape. Bloom occurs in summer although first year plants may not bloom until fall.
  • Leaves:
    Leaf Color:
    Green
    Leaf Feel:
    Smooth
    Leaf Value To Gardener:
    Showy
    Leaf Type:
    Sheath
    Leaf Shape:
    Lanceolate
    Leaf Margin:
    Entire
    Hairs Present:
    No
    Leaf Length:
    > 6 inches
    Leaf Description:
    The leaves of each stem are green, basal, with narrow leaf blades 10 inches long; ascending from the stems. The leaf blades are smooth, and flat with margins that roll upward. The sheaths of young leaves are light green and become tan to brown and shredded over time.
  • Stem:
    Stem Color:
    Green
    Stem Is Aromatic:
    No
    Stem Cross Section:
    Round
    Stem Form:
    Straight
    Stem Surface:
    Smooth (glabrous)
    Stem Description:
    Erect stems, light green, slender, glabrous, and unbranched.
  • Landscape:
    Landscape Location:
    Container
    Naturalized Area
    Pond
    Riparian
    Landscape Theme:
    Native Garden
    Rain Garden
    Water Garden
    Design Feature:
    Mass Planting
    Resistance To Challenges:
    Drought
    Erosion
    Wet Soil
    Problems:
    Weedy