Spruce7 Gallon Colorado blue spruce, also called blue spruce, is a coniferous evergreen tree in the pine family with sharp, short needles, a pyramid shape with silvery blue foliage color, and commonly used as a Christmas tree. Common Name Blue spruce, green spruce, white spruce, Colorado spruce, Colorado blue spruce Botanical Name Picea pungens Family Pinaceae Plant Type Tree Mature Size 50 75 ft. high, 15 20 ft. wide. Sun Exposure Full Soil Type Loamy,