Like firs (Abies), spruces are pyramidal trees, with branches arranged in neat tiers. Unlike firs, however, their cones hang down, and their needles are stiffer and attached to branches by small pegs that remain behind after the needles drop. Most spruces are tall timber trees, but dwarf varieties are lovely in home gardens. Plants have shallow root systems and so need a reasonably cool location. Spruces generally grow best where summers are cool or mild; most suffer in heat and humidity. P. pungens tolerates dry conditions better than the other species.
Spruces can be grown in containers for years as living Christmas trees and moved indoors for up to a week. In coldest climates, move potted trees to a protected location for winter.
Check spruces for small, dull green aphids in winter; if they’re present, take control measures at that time to prevent defoliation in spring. Pine needle scale (look for flat, white scale insects on needles) may encourage sooty mold. In Rocky Mountain states, spruces may be bothered by spider mites and tussock moths. Cooley spruce gall adelgid is an aphidlike insect that attacks many spruce trees, especially in the Pacific Northwest and mountain areas. Its feeding causes green, conelike galls to form at ends of new growth. These galls gradually turn light purplish tan and then brown by autumn. Douglas fir is an alternate host for these pests, but it doesn’t develop galls. Contact your local Cooperative Extension Office for control measures.
Native to Alaska and other parts of northern North America. Forms an irregular column to 30–50 ft. tall and 6–10 ft. wide. Bluish green needles. Tolerates cold, wet soils. ‘Nana’ is a choice compact variety (to 3 ft. tall and 4–6 ft. wide) with blue-gray foliage.
Shrub or tree, native to western North America. Grows to 3–15 ft. tall and wide, often with redd...
Native to Alaska and other parts of northern North America. Forms an irregular column to 30–50 f...
These many-stemmed, thornless shrubs grow to 3–5 ft. tall and wide, depending on vigor and varie...