Picea pungens 'Montgomery'
Montgomery blue spruce
Central and southern Rocky Mountains
Overview
'Montgomery' is a dwarf cultivar of Picea pungens with a dense, broadly conical to globe-shaped habit. Mature plants reach 3-5 feet (90-150 cm) tall and 3-5 feet (90-150 cm) wide at 10 years, eventually reaching 6-8 feet (1.8-2.4 m) tall and 5-7 feet (1.5-2.1 m) wide at 30 years. Growth rate is 2-4 inches (5-10 cm) per year. Needles four-sided, stiff, sharp-pointed, 0.7-1.2 inches (18-30 mm) long, silvery-blue with a heavy waxy bloom that wears off older needles. Color is most saturated in full sun and on needles 2-3 years old. New growth emerges silver-blue in May-June. Branches densely arranged, holding their structure without staking. Bark grey-brown, becoming scaly on the older central stem. Cones are uncommon on dwarf cultivars of this size; when present, female cones cylindrical, 2-3 inches (5-7.5 cm) long, papery-scaled. Susceptible to spruce spider mite, Cytospora canker, and needle cast fungi during summer humidity, particularly in zones warmer than 6.
Native Range
The species Picea pungens is native to the central and southern Rocky Mountains, from Wyoming and Idaho south through Colorado to New Mexico, growing in mountain stream valleys at 6,000-11,000 feet (1,800-3,400 m) elevation. The cultivar 'Montgomery' was selected from a seedling on the estate of Colonel R. H. Montgomery in Greenwich, Connecticut, in the early 20th century, and was donated to the New York Botanical Garden in 1949.Suggested Uses
Used in foundation plantings, rock gardens, and conifer collections, with mature spread of 5-7 feet (1.5-2.1 m) at 30 years. Spaced 5-7 feet (1.5-2.1 m) apart when planted in groups. Suited to container culture in pots of at least 25 gallons (95 L) for the first 15 years before transplanting in-ground.How to Identify
Appearance
Size & Dimensions
Height3' - 8'
Width/Spread3' - 7'
Colors
Foliage Colors
Fall Foliage Colors
Bloom Information
Spruces produce wind-pollinated cones rather than flowers. Pollen and seed cones are uncommon on dwarf cultivars of this size; on plants 15+ years old, male cones reddish in May and female cones cylindrical, 2-3 inches (5-7.5 cm) at maturity. Seasonal interest comes from the silvery-blue foliage rather than from cones.
Detailed Descriptions
Foliage Description
silvery-blueGrowing Conditions
Sun Requirements
Requires 6-12 hours of direct sunlight daily
• Full Sun: 6+ hours of direct sunlight
• Partial Shade: 3-6 hours of direct sunlight
• Full Shade: Less than 3 hours of direct sunlight
Care & Maintenance
Care Guide
Establish in well-drained acidic to neutral soil (pH 5.0-7.0) with full sun exposure of at least 6 hours daily; full sun is required for the strongest blue color. Water deeply once per week during the first two growing seasons; established plants tolerate drought, but blue color fades during extended drought. Spruce spider mite (Oligonychus ununguis) feeds on needles in hot, dry summers and is the principal pest in zones 5-7. Cytospora canker (Leucostoma kunzei) and needle cast (Rhizosphaera kalkhoffii) cause branch dieback and needle drop, particularly in humid summers and in shaded plantings. Tolerates urban conditions and cold winters to -40°F (-40°C); performance declines in zones warmer than 7.Pruning
Spruces do not regenerate from old wood; pruning is limited to removal of dead, broken, or diseased branches at any time of year. The dense globular form requires no shaping. Light tip pruning of new growth in late spring can be used to maintain compactness, with cuts no deeper than the current season's extension.Pruning Schedule
J
F
M
A
M
J
J
A
S
O
N
D
late spring
Container Growing
✓ Suitable for container growing
Minimum container size: 25 gallons