December 2020: Yukon Blue Spruce
Longmont Colorado landscapes – plant of the month
Yukon Blue Spruce or Picea glauca ‘Yukon Blue’ is another small garden evergreen cultivar from Iseli Nursery that this landscaper loves to plant. A medium growth rate, silver-blue short needles, and an upright growth habit make this White Spruce an attractive focal point in any smaller yard. An evergreen of this size is well suited for smaller landscapes where a large, full-size evergreen tree is not appropriate. Yukon Blue will get to be about 12’-15’ high or slightly taller and 6-‘8’ wide at the base, and will maintain a very conical shape.
Like most small evergreen trees, it prefers moist, well-drained soil, though it can handle some of the more clay soils in our Longmont Colorado Landscapes. When planting, amend the soil well, but mix some of the clay back in with the amended soil to prevent root spiraling in the hole. Water well at first, but do not overwater when newly planted. Evergreens can handle the dry conditions longer than newly planted deciduous trees. Once established, it can handle more water, but no evergreen likes to have it’s feet wet continuously, so don’t plant in a soggy location. It likes full sun but can handle partial shade conditions as well. Mulch as one would any other new planting. No pruning is necessary.
White Spruce is native to the northern boreal forests of North America and, thus, is quite cold tolerant. This cultivar is hardy for sure to zone 4, possibly zone 3, so it is well suited for Colorado landscapes. The female cones are attractive, but not overly abundant. The bark is thin, gray, and scaly. Spruce bud moth and Spruce beetle can be common predators, but healthy trees can resist those predators. Spruce beetle is on the decline in Colorado at the moment. Plant one or three in your landscape soon!