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Irish Juniper

Juniperus communis (jew-NIP-er-us KOM-yoo-nis)

Family: Cupressaceae Unknown Understory (15-40 ft)

Irish juniper or 'Hibernica' is a large, needled, evergreen shrub, cultivar in the Cupressaceae (cypress) family. It grows as a dense, upright narrow column that becomes broader and conical with age from 5 to 15 feet tall and 2 to 4 feet wide. The branch tips are stiff and erect. Confers do not bear flowers, but the short needles are tightly crowded on the twig, 3 at a whorl, and fleshy seed cones, bluish and berry-like, create a winter interest. Male and female cones are produced on separate plants. Female plants produce 1/2 inch wide, fleshy, fruit-like seed cones commonly referred to as juniper berries. The plant is low-maintenance and requires little to no pruning. Plant in the full sun in well-drained soil. It is resistant to drought once established and is not often browsed by deer. Irish Juniper does well in sandy, loamy, and clay soils, but prefers medium moisture, well-drained soil in full sun. It will tolerate heavy clay, nutritionally poor soils, and very acid and very alkaline soils. It can grow in semi-shade (light woodland). Established plants tolerate cold temperatures as well as heat and humidity. Insects, Diseases, and Other Plant Problems: Insects that may damage this juniper include bagworms, webworms, and scale. Blight and rust issues are common on junipers The Clemson Cooperative Extension Home and Garden Information Center has a factsheet on common juniper diseases and insect pests. More information on Juniperus communis var. communis .

Source: NC State Extension Gardener Plant Toolbox ↗ NC State Extension Gardener Plant Toolbox, 54 attributes.

How it fits the guild

Guild layer 2 - Understory (15-40 ft) Optimal soil pH Acid (<6.0); Alkaline (>8.0); Neutral (6.0-8.0)
See companions & conflicts ↓

Companions & Conflicts

Curated pairwise relationships between this plant and others in the library — who feeds whom, who competes, who confuses the pests. Green reads as a good pairing, red as one to avoid.

No curated interactions recorded for this species yet.

Also noted by NC State

Related species the NC State Plant Toolbox flags for this plant — look-alikes to tell apart, and plants that play a similar role in a planting. Ones we carry in the library are linked.

Full plant profile

Growing Conditions
Plant type
Shrub
Life cycle
Woody
USDA zones
2a, 2b, 3a, 3b, 4a, 4b, 5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b
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); Sand
Soil pH
Acid (<6.0); Alkaline (>8.0); Neutral (6.0-8.0)
Soil drainage
Good Drainage | Moist
Available space
3 feet-6 feet; 6-feet-12 feet; 12-24 feet
NC region
Coastal; Mountains; Piedmont
Mature size
Height: 5 ft. 0 in. - 15 ft. 0 in. | Width: 2 ft. 0 in. - 4 ft. 0 in.
Growth rate
Slow
Maintenance
Low
Canopy layer
2 - Understory (15-40 ft)
Form & Appearance
Habit / form
Columnar; Conical; Dense; Erect; Multi-stemmed
Texture
Medium
Foliage
Needled Evergreen
Leaf color
Blue; Green; White
Leaf type
Needles
Leaf arrangement
Whorled
Leaf shape
Acicular; Subulate
Leaf feel
Prickly
Leaf value
Fragrant
Hairs present
No
Leaf detail
Bluish-green foliage with a silver band. Dull blue-green when young.
Flower detail
No flowers.
Fruit color
Blue
Fruit type
Berry
Fruit size
< 1 inch long
Fruit detail
No fruits, cones. Fleshy seed cones are bluish and berry-like. On female plants, cones emerge green but gradually ripen by fall to a waxy dark blue to black. Each cone usually contains two or three seeds and ripens in the 2nd or 3rd year.
Bark color
Red/Burgundy
Bark detail
Exfoliating bark is often an attractive reddish-brown.
Wildlife & Ecology
Native status
Unknown
Wildlife value
Birds feed on berries.
Attracts
Songbirds
Food & Medicine
Harvest time
Summer
Fruit type
Berry
Landscape Use
Landscape location
Naturalized Area; Vertical Spaces; Woodland
Landscape theme
Children's Garden
Design feature
Border
Garden tags
#drought tolerant #evergreen #deer resistant #needled evergreen #vertical spaces #border back #columnar #fragrant leaves #wildlife friendly
Problems & Resistance
Insect problems
Juniper Webworm; Juniper Pest Management Calendar; Juniper Tip Dwarf Mite; Juniper Scale Insect; Pests of Conifers
Resistant to
Deer; Drought; Salt
Poison severity
Low
Poison parts
Fruits; Leaves; Seeds
Poison symptoms
Low toxicity if eaten. Large amounts may cause diarrhea.
Toxic principle
Volatile oils including thujone.
Contact dermatitis
No
Toxicity summary
Low severity poison; parts: Fruits; Leaves; Seeds

Planted at Hunnicutt

Nobody’s planted this one yet.