What is the correct botanical name for the species known as Blue Rug Juniper?

The correct botanical name for Blue Rug Juniper is indeed Juniperus horizontalis 'Wiltonii'. This name indicates that it is a cultivar of the species Juniperus horizontalis, commonly referred to as ground cedar or creeping juniper. The 'Wiltonii' designation specifies this particular cultivar, which is known for its dense, low-growing habit and attractive blue-green foliage that has a silvery hue, making it a popular choice for ground cover in landscapes.

Understanding the naming convention is crucial in botany. The genus name (Juniperus) is followed by the species name (horizontalis), and then, if applicable, the cultivar name (Wiltonii), which helps differentiate it from other species or cultivars within the same genus. This precise classification is essential for correct identification, propagation, and care of plants.

The other options provided represent different species or cultivars of junipers. For example, Juniperus conferta 'Blue Pacific' is a different species known for its coastal attributes, while Juniperus procumbens 'Nana' is a dwarf form of a species that grows in a different manner and has distinct characteristics. Thus, understanding these distinctions is vital for horticultural accuracy.