Juniperus horizontalis 'Wiltonii' is a dense, compact, slow-growing, very flat selection of creeping juniper with trailing branches and attractive, silver-blue foliage. It is arguably the most popular groundcover juniper in the nursery trade. After 10 years of growth, a mature specimen will measure 6 to 10 feet (2 - 3 m) wide, but only a couple of inches (2 - 3 cm) high, an annual lateral growth rate of 7 to 10 inches (18 - 25 cm).
This cultivar originated as a natural mutation, found in 1914 on the island of Vinalhaven, Maine, by Jacob van Heiningen of South Wilton, Connecticut, USA. It is sometimes seen listed as 'Blue Rug' in the nursery trade.
