Colorado Blue Spruce

Native only to the Rocky Mountain states, the blue spruce (Picea pungens) is one of our most beautiful evergreens and has been planted widely throughout Iowa for ornamental use. It is a hardy tree with compact, dense foliage and a slow growth rate.

colorado blue spruce tree
Colorado Blue Spruce Tree - Photo by Paul Wray, Iowa State University

Hardiness: Zones 3 through 7

Growth Rate: Slow to Moderate (30-50 feet after 35-50 years)

Mature Shape: Regular narrow to broad pyramid with horizontal stiff branches to the ground. Very dense. Often becomes open, poor, and dingy in old age.

Height: 30 to 60 feet under average landscape conditions
(90 to 135 feet in the wild)

Width: 10 to 20 feet under average landscape conditions
(20 to 30 feet in the wild)

Site Requirements: The blue spruce prefer rich, moist soil in full sunlight, but are very adaptable.

Flowering Dates: April - June

Seed Dispersal Dates: Fall - Winter

Seed Bearing Age: 20 years; optimum seed production 50 to 150 years

Seed Bearing Frequency: Yields full crops of cones every 2 or 3 years. 

Seed Stratification: Warm stratification for 16 days at 68°F to 85°F

colorado blue spruce needles
Colorado Blue Spruce Leaves - Photo by Paul Wray, Iowa State University

Needles are single, very stiff and sharp pointed, angular or four-sided, 1 to 1-1/4 inches long, with a bluish color especially distinct on the new growth. Cones are light brown and cylindrical, very sharp and 2-1/2 to 4-1/2 inches long. The bark is silvery gray-brown and composed of many thin scales divided into vertical ridges. Colorado blue spruce grow 75 to 100 feet tall. They make good winter cover for wildlife.

Diseases that Can Affect Colorado Blue Spruce

Insects that Can Affect Colorado Blue Spruce