About Colorado Blue Spruce: Seed from San Juan National Forest. Grows to 100 feet. Stiff, silvery-blue to green needles are 1 inch long. Grown from best seed source for blue color. However, not all seedlings will be blue.”King of the Ornamentals”. Handsome ornamental specimen in single planting or dense, colorful screen or windbreak, space 6 feet apart. Ordinary soil, average moisture.