Diablo Ninebark vs Mountain Alder - TreeTime.ca

Diablo Ninebark vs Mountain Alder

Physocarpus opulifolius Diablo

Alnus incana subsp. tenuifolia

COMING SOON

(new stock expected: fall of 2026)

CUSTOM GROW

Diablo Ninebark
Mountain Alder

Diablo Ninebark is a small, low maintenance, multi-stemmed shrub, that is used to add texture or color to any yard. This plant grows dark purple leaves in the spring and grows slightly faster than Common Ninebark. It features flaky red to brown bark, clusters of white flowers, and long, maple-like leaves. Diablo Ninebark can make a dense and colorful hedge, or it can be an attractive ornamental by itself.

Mountain Alder is a native cold-hardy shrub or small tree often found along streams and in moist forested habitats. Its nitrogen-fixing ability enriches soils and supports surrounding vegetation, while its extensive root system helps stabilize streambanks and slopes. The fast growth rate allows it to establish quickly on disturbed sites, making it especially valuable in reclamation, restoration, and erosion control projects.

Often forming dense thickets, Mountain Alder enhances habitat quality in riparian and upland areas. It provides food and cover for various wildlife, including birds and small mammals. Recognized as an important species for soil and water conservation, it is well suited for riparian planting, naturalization, and ecological restoration.

Note: We use Sitka Alder for Alnus incana subsp. tenuifolia. This species is also known by many other common names, including Grey Alder, River Alder, and others. Please confirm the scientific name to ensure you are ordering the correct plant.

Diablo Ninebark Quick Facts

Mountain Alder Quick Facts

Zone: 3a
Zone: 1a
Height: 2.4 m (8 ft)
Height: 6 m (20 ft)
Spread: 1.8 m (6 ft)
Spread: 3 m (10 ft)
Light: partial shade, full sun
Light: partial shade, full sun
Moisture: dry, normal
Moisture: normal, wet
Growth rate: fast
Growth rate: medium
Life span: short
Life span: medium
Growth form: multi-stemmed, thicket-forming
Spreading: rhizomes - medium, seeds - low, layering - low
Suckering: low
Maintenance: medium


Foliage: reddish-purple
Fall colour: yellow
Bark: brown to red, exfoliating
Bark: smooth, gray to brown
Flowers: white
Berries: red
Seeds: inflated seed capsules
Hybrid: no
Hybrid: no
Catkins: no
Catkins: yes


Native to: AB, BC, SK, YT, NT
Other Names: eastern ninebark, purple ninebark
Other Names: river alder, speckled alder, thin-leaved alder, thinleaf alder, western river alder