Blue Carpet juniper

Sun

Full sun gives the strongest blue colour and densest growth. Light shade is tolerated, but growth becomes looser.

Water

Water regularly during the first growing season, allowing the soil surface to dry between soakings. Once established, water during prolonged drought; avoid constantly damp soil.

Soil

Well-drained sandy, gravelly or loamy soil, from slightly acidic to alkaline. Avoid waterlogged ground and heavy clay unless drainage is improved.

Height

1-2 ft (0.3-0.6 m)

Spread

5-8 ft (1.5-2.4 m)

Foliage

Evergreen. Dense, pointed, needle-like leaves in silver-blue to blue-grey, sometimes developing a purplish cast in cold weather. The foliage is prickly to handle.

Growth

Slow to moderate; allow several years for plants to form a broad, joined cover.

Care needed

Low

• Deer resistant
• Drought tolerant
• Cold hardy
• Wildlife

Northern hemisphere months. In Australia, shift them by six.

Difficulty

Easy

Toughness

Very tough

Pick your zone, country, light and whether you have pets.

1. Planting day

   1.5 ft (0.45 m)

   full size

About 7 years to full size.

From a typical nursery size, at an average rate for this kind of plant. A rule of thumb, not a forecast.

Cats and dogs

Mildly toxic: may upset a stomach

Growth rate

Slow

• Water deeply through the first growing season whenever the root zone begins to dry.
• Leave enough space for the mature spread rather than relying on repeated trimming.
• Apply a thin mulch, keeping it clear of the crown and lower stems.
• Feed lightly in spring only if growth is weak or the soil is very poor; avoid heavy nitrogen feeding.
• Keep fallen leaves and weeds from accumulating within the branches.

Pruning. In spring, remove dead, damaged or diseased shoots and shorten wayward branches back to a leafy side shoot. Do not cut into bare old wood, which usually will not regrow, or shear the plant into a tight shape.

Early spring

Check for winter damage and remove dead shoots in dry weather.

Spring

Plant in well-drained ground, water thoroughly and mulch without covering the crown.

Late spring

Check shoot tips for browning and inspect affected branches for blight or mites.

Summer

Water young plants during dry spells; water established plants only during prolonged drought.

Late summer

Take semi-ripe cuttings if you want to propagate the cultivar.

Autumn

Clear fallen leaves from the branches and check that water drains away freely.

• Plant across sunny banks for low evergreen cover, allowing space for each plant to spread.
• Let branches soften the edges of rocks or low retaining walls.
• Combine with upright ornamental grasses for a contrast between a blue horizontal carpet and vertical stems.
• Use in gravel beds with drought-tolerant perennials, keeping their crowns clear of its spreading branches.
• Place beside dark green conifers or purple-leaved shrubs to make its pale blue foliage stand out.

Garden styles it suits: Low-maintenance, Dry gravel garden, Winter interest, Desert / xeriscape, Alpine rock garden and Modern.

Plant it with: Lavender, Catmint, Russian sage, Blue fescue, Stonecrop and Dwarf mountain pine.

Wildlife: The dense branches provide low shelter for small animals and invertebrates. This wind-pollinated conifer offers little nectar value, and cone production on this cultivar should not be relied on as a bird-food source.

• Root rot in wet soil: improve drainage before planting, avoid overwatering and replace badly affected plants rather than replanting in the same wet spot.
• Juniper tip blight: prune affected shoots back to healthy growth in dry weather, clean tools between cuts and avoid overhead watering.
• Spider mites in hot, dry conditions: check for fine webbing and mottled needles; rinse foliage with water and use a locally approved mite treatment if damage continues.
• Winter scorch: water before the ground freezes if autumn has been dry, and protect newly planted shrubs from drying winds; prune dead tips once spring growth reveals the damage.

Do not eat the foliage or berry-like cones. Junipers can cause digestive upset if eaten by people, cats or dogs, and foliage oils may irritate skin; serious poisoning is uncommon after small accidental exposures. Toxicity information specific to this cultivar in horses is limited, so keep it out of grazing areas and do not feed clippings to livestock.

• Blue Star juniper (Juniperus squamata 'Blue Star')

  It has similarly prickly blue foliage but forms a compact, rounded mound rather than a broad, low carpet.

• Blue Rug juniper (Juniperus horizontalis 'Wiltonii')

  It hugs the ground more closely and has finer, mostly scale-like foliage rather than the conspicuous prickly needles of Blue Carpet.

• Blue Pacific shore juniper (Juniperus conferta 'Blue Pacific')

  It also spreads low but has longer, coarser needles and generally greener or blue-green foliage.

Juniperus is the Latin name for juniper, squamata means scaly and refers to the bark, and 'Blue Carpet' describes the cultivar's foliage colour and spreading habit.

Propagation. Take semi-ripe cuttings with a small heel of older wood in late summer and root them in a freely draining medium under humid conditions. Cuttings preserve the cultivar; seedlings will not reliably match it.

Accepted botanical name

Juniperus squamata

Native range

Afghanistan, Assam, China North-Central, China South-Central, China Southeast, East Himalaya, Myanmar, Nepal, Pakistan, Qinghai, Tibet and West Himalaya.

Measured

Average height 650 cm.

Sources: GBIF (CC BY 4.0) and Trefle (CC BY 4.0). The care and design notes are LandscapeGPT's own.