Juniperus horizontalis ‘Wiltonii’
Overview
Uses: Groundcover, slopes and banks, rock gardens, wall edges, and mass plantings.
Benefits: One of the flattest junipers, forming a dense carpet of silvery blue foliage just a few inches tall that takes on a plum tint in winter. Spreads wide to cover ground and hold slopes, and handles heat, drought, and deer.
USDA Hardiness Zones: 3–9
Sun: Full Sun
Life Cycle: Coniferous Shrub
Growth Habit: Spreading — flat, trailing carpet.
Foliage Color: Silvery Blue-Green, with a Plum tint in winter
Mature Height: 4–6 inches
Mature Width: 6–8 feet
Growth Rate: Moderate
Summary
About as flat as an evergreen gets: a silver-blue carpet that keeps widening year after year.
Blue Rug is the classic low creeping juniper, and it has stayed popular for decades because it does one job extremely well. Its long, trailing branches lie nearly flat against the ground, building a dense mat only four to six inches tall that slowly spreads six to eight feet across.
The fine foliage is a cool silvery blue through the growing season. In winter it picks up a purple-plum cast, then returns to blue as spring arrives. That color reads well against stone, gravel, and mulch, and it softens the hard edges of walls, steps, and boulders.
It is at its best on sunny ground that is hard to plant or mow: steep banks, the tops of retaining walls where branches can spill over the edge, rock gardens, and the hot strip along a driveway. Once established it handles heat, drought, and poor soil, and deer usually leave it alone.
Care
Blue Rug Creeping Juniper Care
Plant in full sun. Strong light keeps the color blue and the mat dense; in shade growth turns thin and open.
Creeping juniper prefers lean, well-drained soil and grows well in sand, gravel, and rocky ground. Avoid heavy soil that stays wet, which is the most common cause of decline. Good drainage and open air around the plants also help prevent the twig blight that can brown juniper tips in wet springs.
Water deeply once a week through the first growing season while roots establish. After that, plants tolerate long dry spells and need water only during extended drought. Mulch between new plants to hold moisture and keep weeds out while they spread.
Feeding needs are light. In poor soil, one application of a slow release fertilizer in early spring is enough; in average soil it usually needs none.
Pruning is rarely needed. To keep branches off a walk or lawn edge, trim them in spring back to a point with green foliage, tucking the cut under an overlapping branch so it does not show. Junipers do not regrow from bare wood, so avoid cutting into old, leafless stems.
Size
What Size is the Blue Rug Creeping Juniper for Sale Online?
Our Blue Rug Creeping Juniper ships in a greenhouse-grade grow pot and is appropriately sized for its container at the time of shipment. Plants shipped in late fall or winter may show their plum winter tint, which is normal and returns to blue in spring. If you have specific sizing or planting questions, please contact us.
How Large Does Blue Rug Creeping Juniper Grow?
Expect about 4 to 6 inches tall and 6 to 8 feet wide at maturity, in a flat, trailing carpet. Space plants about 4 to 5 feet apart for groundcover; closer spacing fills in sooner.
Additional Information
What are some common names for this plant?
- Blue Rug juniper
- Wilton carpet juniper
- Creeping juniper
Is Blue Rug Creeping Juniper a native plant?
It is a selection of Juniperus horizontalis, which is native across Canada and the northern United States. Selections like this one are often called nativars: they keep the toughness of the native species while adding traits such as an especially flat habit and blue color. Browse more Native Plants of North America.
Can I walk on it?
Blue Rug looks like a lawn substitute, but it does not handle regular foot traffic. Branches crushed underfoot brown and die back. Where you need a path through a planting, set in stepping stones and let the juniper grow around them. For more low, spreading plants, see our Groundcovers.
Do deer eat Blue Rug Juniper?
Deer usually avoid junipers because of their stiff, aromatic foliage, so Blue Rug is a dependable groundcover where deer pressure is heavy. No plant is completely deer-proof, and hungry deer may still sample new growth in a hard winter. See more Deer-Resistant Shrubs and Evergreens.
