Tsuga mertensiana
A fairly slow-growing evergreen tree, broadly conical in habit, with blue-grey linear leaves around brown shoots and pendulous cones 5–8 cm long with recurved scales, native to the Northwest, highly winter-hardy and often stunted at timberline.
Common Names
Mountain Hemlock, California Mountain Hemlock, Northern Mountain Hemlock, Jeffrey's Mountain Hemlock, Hemlock Spruce
Summary
Mountain Hemlock is a native evergreen conifer of the Pacific Coast mountains, from Alaska to central California. It features a slender, wind-sculpted crown and bluish-green needles arranged radially around the shoots, with two bluish-white stomatal bands on the undersides giving a glaucous appearance; its small pendant cones are cylindrical and about 1–3 inches long when closed. In gardens it grows slowly to around 30 feet tall and 15 feet wide, while wild forms may reach 60–100 feet; it is long-lived, frequently 800+ years, and exhibits a pyramidal to narrow habit with slightly pendulous branch tips.
Cultivation emphasizes moisture and cool summers: it prefers moist, well-drained soil in full sun to partial shade and is hardy to USDA zones 5–8, with a notable intolerance of heat and drought. Practical uses include a suitable single specimen or focal point in rock gardens or small landscapes, and it can be grown in containers; native to the Northwest Cascades, it offers a refined silhouette and year-round interest.
Lifecycle
Perennial
Height
30-100 ft
Spread
10-32 feet
Hardiness Zones
Zones 4-9
Sunlight Requirements
Ideally full sun to partial shade.
Soil Type
Moist, acidic, well-drained soil with rich organic content
Soil Drainage
Well-drained, moist soil
Soil pH
4.2-5.0
Bloom Color
Yellow
Bloom Time
Spring–Summer
Foliage Color
Blue-green to gray-green (year-round)
Fall Foliage Color
No fall foliage color
Leaf Lifecycle
Evergreen needle
Growth Rate
Slow growth
Seasons of Interest
Spring, Summer, Fall, Winter
Propagation Methods
Seeds, Cuttings, Layering
Attracts Wildlife
Attracts birds
Taxonomy
- Taxonomic Rank
- Species
- Author
- (Bong.) Carrière
- Publication
- Traité Gén. Conif. ed. 250. (1867)
Superior Taxa
- Kingdom
- Plantae
- Subkingdom
- Pteridobiotina
- Phylum
- Pinophyta
- Class
- Pinopsida
- Subclass
- Pinidae
- Order
- Pinales
- Family
- Pinaceae
- Genus
- Tsuga
Inferior Taxa
Tsuga mertensiana subsp. grandicona Tsuga mertensiana subsp. mertensiana
Synonyms
Tsuga pattoniana Tsuga mertensiana var. macrophylla Tsuga pattonii Pinus mertensiana Picea mertensiana Picea californica Abies mertensiana Abies pattonii Abies williamsonii Hesperopeuce mertensiana Pinus pattoniana Tsuga williamsonii Picea hookeriana Tsugaxpicea hookeriana Abies pattoniana Abies taxifolia Hesperopeuce pattoniana