Colorado blue spruce, also called blue spruce (Picea pungens) grows at a slow to medium rate of less than 12 inches per year and up to 24 inches per year when young. It can take 35 to 50 years for a Colorado blue spruce to grow 30 to 50 feet.
Hereof, why are my blue spruce trees turning brown?
Later the needles turn brown or purplish brown on blue spruce. Mites are a potential problem on all spruce trees. As spider mites feed on the needles with their sucking mouth parts, they cause the needles to turn dull and eventually become yellowish green and drop.
What causes a blue spruce to die?
Cytospora canker is a fungus that attacks spruces and causes branch death. Another fungal disease, Rhizospaera needlecast, causes the inner needles to die off, leaving only green tips on branches. Over time, this can cause branch death.
How far apart do you plant blue spruce trees?
This is the one time to plant the trees in a dense row, creating a wall of greenery. You can plant American arborvitae trees (Thuja occidentalis) 3 feet apart, but most evergreens need more space. For instance, cedars and junipers need 6 to 8 feet between them, while pines and spruces need 10 to 12 feet of spacing.