Picea pungens
Colorado Spruce
Mature Size, Growth, Longevity
Average mature size of 30-60' tall and 10-20' wide in the landscape, species can grow to 90-135' tall and 20-30' wide in wild, some cultivars much shorter. Very stiff and formal in outline. Dense, conical/pyramidal, with horizontal branches to the ground. Slow to moderate growth rate, 30-50' after 35-50 years. Species lives to 400 years in nature under optimal conditions.
Native Range
U.S. Native — Native to Southwestern United States; Rocky Mountains from Colorado to Utah to New Mexico and Wyoming. Introduced about 1862.
Flower and Fruit Details
Flowers are monoecious, male orange, female greenish or reddish-purple. Flowers mostly in upper crown of tree, in bloom May/June. Fruits in cylindrical cones, slightly narrowed at each end, 2-4" (to 5" sometimes) long, 1-1.25" wide, green with violet bloom, pale shining brown when mature. Scales wavy, oval, blunt and jaggedly toothed at apex, on a short stalk.
Leaf and Bark Features
Evergreen: Needles get very sharp and prickly, 0.75-1.25" long, silvery blue-gray to dull green. Much color variation, from blue-green to gray-green to silver-green or just dull green. Needles are 4-sided, w/ stomatal bands, and have an acid taste if chewed. The bark is in large, loose, coarse scales, with a silvery-gray, thin, flaky appearance.
Culture and Care
Prefers rich, moist soil in full sun, although it is more drought tolerant than other spruces. Very adaptable. Requires an acid soil, pH 4.6-6.5. Zones 3-7. More drought-tolerant than most spruces. Avoid wet, poorly drained or flooded sites. Avoid soil compaction. Susceptible to spruce gall aphid, which can cause tips of branches to die, plus spruce budworm and spider mites. Cytospora canker disease may infect lower branches. Needle cast fungus may be a problem. Avoid overhead night watering.
Strengths, Weaknesses, Other Facts
Acceptable in dry climates. Good wildlife value. 4-season interest: Spring, Summer, Fall, Winter. An overused species. Popular as a specimen but hard to combine well with other plants; the use of this plant or a blue-foliage type in the front yard may detract from the rest of the landscape. Considered to be one of the 5 best spruces for general landscape use in the Midwest, East, & Upper South. The blue needle trait is variable, and most blue-needled cultivars are asexually propagated.
Suggested Uses
Often overused in home landscapes as specimens. Can be utilized in hedges, screens, in group plantings or windbreaks.
Taxa and Plants of this Species at BCA
The following taxa are (or were) represented in the collections at Boone County Arboretum. Additional taxa may be available in the trade that are not included here.
Picea pungens // Colorado Spruce, Colorado Blue Spruce ("straight species")
Tree.
-- not currently in our collection --Picea pungens 'Fastigiata' // Columnar Colorado Blue Spruce
Tree. Narrow, upright pyramidal to columnar habit, slowly growing to 10-25' tall and 5-10' wide. Steel blue foliage in a fat cigar shape. Blue new growth becomes more silvery-blue with age. Very low maintenance. Resistant to Verticillium Wilt fungus. Deer and rabbit resistant. Zone 3-7. Good for tight spaces or as a screen. Could be used as a specimen in landscapes, or in place of columnar Junipers. Also used in containers, rock gardens and foundation plantings. Introduced by Iseli Nursery.
BT006292 - BT006296Picea pungens 'Fat Albert' // Fat Albert Colorado Blue Spruce, Fat Albert Spruce
Tree. A good, blue needle color. Has a short, wide, dense, symmetrical, upright pyramidal form, 10-15' tall, but eventually taller, with a broad base over time, 7-10' (or more) wide. Considered semi-dwarf with a slow, uniform growth rate. Foliage more blue, less silver/gray needle color. Grown from cuttings, so it forms an excellent terminal leader, with no need of staking or training. Considered one of the best blue spruces in America. Tolerates rabbits, deer, clay, drought and pollution.
-- not currently in our collection --Picea pungens 'Globosa' // Globe Dwarf Colorado Blue Spruce
Shrub. Slow-growing to 3-4' tall and 4-6' wide, forming a dense, dwarf, compact, flat-topped, rounded bush. A neat, irregular bush, with closely set branches angled outwards and upwards. Needles are stiff and prickly, 0.33-0.5", glaucous green to bluish-white or blue-gray, more or less radially arranged. Full sun. May need sprayed for spider mites in warmer climates. Zones 2-7. Grafted or grown from cuttings. Good for small gardens and in rock gardens. Is probably the same as 'Glauca Globosa'.
Bed 167 - BS009040 - BS009042 - BS009043 - BS009130Picea pungens 'Golden Feathers' // Golden Feathers Colorado Spruce
Tree. Grows 20-40' tall & 10-15' wide, with a somewhat open, narrowly conical habit, which highlights the interesting tiers of branches. New growth starts out a stunning, bright yellow (for about 2 weeks), then becomes more chartreuse, and finally blue-green. Young cones whitish in color. Needs full sun. Selected from seedlings around 1960, introduced by Brotzman's Nursery in Madison, Ohio.
BT001373 - BT001882Picea pungens 'Hoopsii' // Hoopsii Colorado Blue Spruce
Tree. This is the best growing and the overall best of the various blue spruces. Slowly grows to 30-60' tall and 10-20' wide. Densely pyramidal. Spreading branches. It is the bluest of all the spruces. However, it is difficult to propagate. Needles are extremely glaucous, silvery blue to whitish-blue, long, curved, thick, very sharp, pointing forwards, almost hiding the light brown stems. Dr. Michael Dirr, author and plantsman, says this is his "number one choice" amongst the Colorado Blue Spruces.
BT005810 - BT005840 - BT006373Picea pungens 'Lou's Blue' // Lou's Blue Colorado Spruce
Tree. Silvery-blue to blue-green foliage.
BT001242Picea pungens 'Pendula' // Weeping Colorado Blue Spruce
Tree. A specimen plant with silvery-blue needles. Quite variable, with several forms in cultivation. It can be allowed to grow prostrate as a groundcover, or with training, this selection forms an upright tree with cascading growth. When positioned upright, the terminal leader always points back down toward the ground, the branches & branchlets sweep downwards to the ground, forming a silver-blue carpet at the base. Also known as 'Glauca Pendula'. Dutch nursery introduced in 1895.
BT005545