The Colorado blue spruce is an evergreen tree that grows upright to a height of 135 feet and spread of 30 feet. The tree has stiff needle foliage in the color of blue-green or silver-green. Colorado blue spruce is hardy to plant in U.S. Department of Agriculture growing zones 3 through 8 and grows best when planted singly due to its size. The tree does not grow well as a privacy screen because the branches droop as it ages.
Select a planting location for the Colorado blue spruce that has nutrient-rich and well-draining soil. The area should offer full sun to partial shade light conditions with a minimum of six hours direct sunlight.
Test the soil pH to verify that it is acidic at a level of 3.7 to 6.5. Work ground rock sulfur into the soil two to four weeks prior to planting to lower the pH number if needed. Water the soil well after applying the amendment.
Soak the root ball with water several hours prior to planting. Place the tree in a shaded location until it is ready to plant to prevent the root ball from drying.
Dig a hole for the Colorado blue spruce that is three times as wide and the same depth as the root ball. Rough the sides of the hole with a shovel to make it easy for the roots to penetrate the surrounding soil.
Remove the Colorado blue spruce tree from the container or burlap wrapping, and set it into the hole so that the top of the root ball is at ground level. Remove twine that may be wrapped around the roots. Compacted roots should be loosened by gently pulling out the bottom roots before placing the tree in the hole.
Fill half of the hole with soil, and fill the remaining area with water to pack the soil. Fill the remaining hole area with soil, and gently pack in place. Water the tree generously to eliminate air pockets around the roots.
Sprinkle a high-phosphorous root-promoting fertilizer over the root ball area to promote root growth and establishment. Water the area well to assist with absorption of the fertilizer.