Hollywood juniper had formerly been the only popular juniper of tree form. As it became less popular during the past few decades, cultivars of the once obscure Rocky Mountain juniper, Juniperus scopulorum, became more popular. Also, a few more modern cultivars became available. Now, the once overly common Hollywood juniper is quite uncommon.
Rocky Mountain juniper is naturally rather grayish for protection from the harsh exposure of the high elevations which it inhabits. Cultivars are grayer, bluish or silvery, and mostly develop symmetrically conical form. Old specimens that were initially conical eventually grow as small trees with rounded and relatively dense canopies, perhaps on bare trunks.
‘Skyrocket’ and ‘Blue Arrow’ are very narrow like Italian cypress that grow only fifteen feet tall. ‘Wichita Blue’ and ‘Moonglow’ are stoutly conical. ‘Blue Arrow’ and ‘Wichita Blue’ are bluish green. ‘Skyrocket’ and ‘Moonglow’ are silvery gray. Established specimens do not require much water, but develop better foliar color with warmth and occasional watering.