Juniperus horizontalis 'Dunvegan Blue' is a creeping form with silvery Blue juvenile foliage turning purple in autumn. (Humphrey Welch and Gordon Haddow in The World Checklist of Conifers)
This is known to be currently the hardiest of the Blue spreading junipers.
Found by J.A. Wallace on the bank of the Peace River, near Dunvegan, Alberta, Canada in 1959. The Agriculture Canada research station at Beaverlodge, Alberta is also associated with this cultivar.