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Trailing juniper is a low shrub or ground cover-type evergreen, native to North America.  It can be especially attractive trailing over ledges or retaining walls and very useful on slopes. Junipers are cold-hardy, durable and adaptable plants that can bring year-round color to a dry, alkaline, or windy site. The foliage of scale-like needles is attractive but prickly. In late summer and fall, many junipers have blue-green berry-like fruits, actually modified cones, that attract birds.  Junipers are widely used in bonsai, and are rugged and useful landscape plants. Because they are quite salt-tolerant, they can be used near roads, driveways and sidewalks.  This species is native to the Chicago Region according to Swink and Wilhelm’s Plants of the Chicago Region, with updates made according to current research.  

  • Family (English) Cypress
  • Family (botanic) Cupressaceae
  • Tree or plant type Ground cover, Shrub
  • Native locale Chicago area, Illinois, North America
  • Size range Large plant (more than 24 inches), Low-growing shrub (under 3 feet), Medium plant (12-24 inches), Small plant (6-12 inches), Small shrub (3-5 feet)
  • Light exposure Full sun (6 hrs direct light daily), Partial sun / shade (4-6 hrs light daily)
  • Hardiness zones Zone 3, Zone 4, Zone 5 (Chicago), Zone 6, Zone 7, Zone 8, Zone 9
  • Soil preference Dry soil, Sandy soil
  • Tolerances Alkaline soil, Clay soil, Dry sites, Occasional drought, Road salt
  • Season of interest early fall, early spring, early summer, early winter, late fall, late spring, late summer, late winter, mid fall, mid spring, midsummer, midwinter
  • Flower color and fragrance Inconspicuous
  • Shape or form Creeping
  • Growth rate Moderate, Slow

Size and Form: 

Size can vary by cultivar.  This plant is usually under 2 feet tall, but can spread 4 to 8 feet.  Can be utilized as a low-growing shrub or trailing ground cover.  Trailing ground covers have trailing stems that spread out from a central root system.  These stems spread out horizontally over the ground, but do not root to the ground.

Native geographic location and habitat: 

C-Value: 10.  Found in dunes, slopes and other dry sites in the Chicago region, Canada and isolated areas in the United States.

Attracts birds & butterflies: 

The fruits are attractive to a variety of bird species.

Bark color and texture: 

Bark is brown and peeling  with inner red color; most stems and branches are trailing. 

Leaf or needle arrangement, size, shape, and texture: 

There are two types of needles: short, appressed silvery-blue foliage (needle-like and/or scale-like) and awl-shaped, pointed leaves.

Flower arrangement, shape, and size: 

Male and female flowers on separate plants; both inconspicuous.

Fruit, cone, nut, and seed descriptions: 

Female plants produce berry-shaped cones that ripen to a bluish color.

Plant care:

Trailing juniper grows best in dry, well-drained soil in full sun. Established plants withstand drought and wind. Salt-tolerant. Female plants produce berry-shaped cones that ripen to a bluish color, but nurseries often do not sell these shrubs with the gender known.

List of pests, diseases, and tolerances: 

Susceptible to juniper tip-blight diseases that can cause branch die-back. Bagworm can be a problem.

These plants are cultivars of a species that is native to the Chicago Region according to Swink and Wilhelm’s Plants of the Chicago Region, with updates made according to current research. Cultivars are plants produced in cultivation by selective breeding or via vegetative propagation from wild plants identified to have desirable traits.

Bar Harbor trailing juniper (Juniperus horizontalis ‘Bar Harbor’): 

This is a low, spreading cultivar, 1 foot high and 6 to 8 feet wide. Blue-green foliage turns purple in winter (more so than Blue Rug).   Male cultivar.

Blue Chip trailing juniper (Juniperus horizontalis ‘Blue Chip’):

A low, spreading shrub, up to 1 foot high and 8 to 10 feet wide. Bluish-green foliage turns purple in winter. Susceptible to phomopsis tip-blight.

Blue Rug trailing juniper (Juniperus horizontalis ‘Wiltonii’):

Very low, flat, spreading shrub, just  6 inches high and up to 8 feet wide. Dense silvery-blue foliage turns light purplish in winter. Plants of this female cultivar produce berry-shaped cones that ripen to a bluish color. Resistant to cedar rust but susceptible to juniper tip-blight diseases.

Hughes trailing juniper (Juniperus horizontalis ‘Hughes’):

A low, spreading shrub, 1 1/2 feet high and 6 to 8 feet wide. Silvery blue foliage maintains color in winter.   Resistant to cedar rust but susceptible to juniper tip-blight diseases. Bagworm can be a problem.

Icee Blue® trailing juniper  (Juniperus horizontalis ‘Monber’):

Very low, flat, spreading shrub, just 6 inches high and up to 8 feet wide. Dense, silvery-blue foliage. Resistant to cedar rust but susceptible to juniper tip-blight diseases.

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