Shore Juniper Juniperus conferta

Shore juniper comes off the coastal dunes of Japan and Korea, and it grows the way dune plants grow: flat and wide rather than up, laying down dense radiating sprays of bright green needle foliage that knit into a continuous mat. The distinguishing quality is how sharply prickly that mat is, which is both why it suppresses weeds so effectively and why you weed the bed early rather than reaching into it later. Use it on sandy banks, over rock terraces, and anywhere exposed ground needs binding.

Sand, salt and airflow

Full sun, poor sandy soil and salt wind are exactly its conditions, and it takes full coastal exposure without complaint. Space plants roughly 700mm to 1m apart across a bank and they will run together into cover; plant into the native soil rather than a rich imported mix, and mulch with gravel or coarse bark kept clear of the stems. Once established it needs very little water and almost no attention. On a steep bank it holds the surface well, which is the main reason it turns up on dune stabilisation jobs and difficult coastal batters. It also copes with the glare and reflected heat off rock and paving that burns off softer groundcovers, and it holds its green through winter rather than bronzing.

The one real failure mode is not drought or cold, it is wet feet combined with still humid air. In heavy clay or a poorly drained bed it browns out in patches from root rot, and through a humid summer the interior dies back where nothing ever dries out. Mound the bed or plant on a slope, keep irrigation modest, and give it airflow rather than a sheltered corner.

Green, gold or soft-needled

The direct alternative is Shore Juniper - Juniperus conferta All Gold, which has the same low spreading habit with gold-cast new growth. Take the gold form as a colour break in a rockery or against dark foliage, and take the plain green species for large areas, because it is the more vigorous of the two and knits into even cover across a large bank sooner. If the planting is somewhere people brush past, Juniperus taxifolia Lutchuensis is the softer-needled option and drapes more gracefully over a wall edge, though it covers ground more slowly. All three sit in low maintenance.

Trim the tips, never the brown wood

Shorten green shoot tips in spring to keep the mat inside its boundaries, and tidy again in early autumn if it has run over an edge. Cutting back into the bare brown wood inside the plant leaves a permanent hole, since junipers will not reshoot from it, so reduce a plant that has outgrown its space by removing whole stems back to a junction instead of shearing the surface. Feed lightly in early spring with a slow-release fertiliser and water it in. Wear thick gloves and long sleeves for any of this work.

Choosing a size

This plant is available in 5 sizes, from 125mm up to 300mm, priced from $16.95 to $88.95 per plant. The size shown is the pot the plant arrives in, which is the rootball, not the height of the plant. These are younger plants, priced for planting in quantity, and they establish quickly once in the ground. Not sure which to choose? Read our guide to low water gardens.