Glauca Juniper

Glauca Juniper (Juniperus horizontalis 'Glauca') is a carpeting conifer that stays around 30cm high and spreads to about 2.5m. The foliage is a soft blue grey that holds its colour through summer heat and winter frost alike. On a dry bank or rockery, where lawn gives up and mulch washes away, it is one of the few plants that will simply cover the ground.

Why you'll love it

• Real weed suppression. The prostrate growth closes over the soil, so once the plants knit together there is little weeding left.
• Colour with no flowers involved. The blue grey tone is constant, a useful foil for green shrubs, stone and grey render.
• Tough where little else holds. Frost hardy, drought tolerant, salt tolerant and content in poor, thin, rocky soil.
• No maintenance routine. It spreads at its own pace and asks for no clipping, feeding or shaping.

Where it works best

Groundcover and mass planting. Plant 1m apart for full coverage, roughly one plant per square metre, so a pack of ten covers about 10 square metres.

Slopes and retaining walls. Roots knit into a bank and hold soil that would otherwise wash, and the branches spill over a wall edge to soften it.

Rockeries and coastal gardens. It belongs among gravel and stone, and salt laden wind does not burn it, so exposed coastal beds suit it.

Growing Glauca Juniper in Australia

Position and climate. Full sun, the more the better for colour and density. It suits cool temperate, warm temperate, Mediterranean and arid gardens, so most of the southern states and the dry inland. In humid subtropical and tropical gardens it is unreliable, because wet summer air causes fungal dieback.

Soil. Drainage decides everything. Sandy, rocky and poor soils are ideal, while heavy clay that stays wet will kill it. On clay, build the bed up and plant high.

Water and feed. Water weekly through the first summer, then only in a long dry spell. Feeding is rarely needed; a light complete fertiliser in early spring is plenty.

Pruning. Very little. Shorten a wayward branch back to a side shoot inside the plant, and never cut into bare brown wood, because junipers do not reshoot from it.

What to expect when it arrives

It is grown in one size, 140mm in a pack of 10, the natural quantity for the job: ten plants at 1m spacing cover about 10 square metres of bank or bed. Plants arrive small and low rather than already spreading, so set out the layout before digging.

Expect the mat to close over in three to four seasons, faster with water through the first two summers. Delivered Australia wide, with delivery from $29.95 and a minimum order of $300 before delivery, and every plant is covered by our 30 day healthy plant guarantee.

Plant care guides and related reading

• Growing and maintaining conifers
• Browse the full groundcover range
• Compare plants for retaining walls and slopes

Common questions

How far apart should I plant it?

One metre apart for a continuous carpet. Each plant reaches about 2.5m across in time, so wider spacing still closes, it just leaves bare soil to weed for longer.

How quickly does it cover the ground?

Expect three to four seasons for a closed mat at 1m spacing. Growth is steady rather than fast, and regular water through the first two summers makes a noticeable difference.

Can I cut it back if it spreads too far?

Only lightly. Trim branches back to a side shoot within the green growth, because cutting into bare wood leaves a permanent hole. Allow the full 2.5m spread when you plan.

Can I walk on it?

No, it is not a lawn substitute. Foot traffic crushes the foliage and it does not spring back, so run steppers or a path through a large planting instead.