The Colorado blue spruce (Picea pungens) is cherished as an ornamental landscaping tree, says the Ohio Department of Natural Resources. The Colorado blue spruce grows native to parts of the Rocky Mountain States in the western United States. The tree has many admirable attributes that also make it one of the most desirable Christmas trees. The tree now comes in various hybrids that offer homeowners a selection of forms, colors and sizes for their property.
In natural settings, the pyramid-shaped Colorado blue spruce sprouts up to heights between 65 and 115 feet, with trunk widths that can approach 3 feet on the largest of these specimens. The Colorado blue spruce has blue-gray to silver-blue foliage, with the needles being as long as 1.5 inches; the needles nearer the top of the tree are shorter than those on the bottom branches. The needles are quite sharp and possess four sides more easily noticed in cross-section than when looking at them from other angles. The needles will point outward from the twig upon which they grow, rather than angling away from the branch.
The native range of the Colorado blue spruce extends from western regions of Wyoming and eastern parts of Idaho south through the middle of Colorado and into central portions of Utah. The spruce grows as far south as New Mexico and parts of Arizona. The tree can grow at elevations as high as 11,000 feet. The species typically grows near mountain streams.
Choose a full or partial sun location that has damp and acidic soil for your Colorado blue spruce, but be sure the spot drains well and does not get too wet during the course of the year. The tree will handle poor quality soil if need be and will withstand periods of drought. Oddly enough, despite its native range so far up in the mountains, Colorado blue spruce holds up when exposed to pollution from car exhausts.
As many as 70 hybrids of Colorado blue spruce exist, notes the National Christmas Tree Association. Among them are the 'Montgomery', a dwarf cultivar with thick branches and blue needles. The 'Thompson' and 'Hoopsii'' varieties feature steel-blue foliage, while the Foxtail' has a more bushy form with blue needles. Another smaller version of the Colorado blue spruce is the 'Hoops Blue'. The 'Moerheim' is compact but still has the trademark blue color.
The fact that where it grows is so hard to access has helped Colorado blue spruce from becoming a major source of timber. Many people will choose this tree as a living Christmas tree, putting it in their yard after the holidays. The cones of Colorado blue spruce have light and flexible scales, turn brown and measure from 2.5 to 4 inches long. The tree avoids blow downs by putting down a deep taproot. In its natural setting, this type of spruce often grows alongside Engelmann spruce and Douglas fir.