Narrowleaf Cottonwood Plant Care

Narrowleaf Cottonwood (Populus angustifolia) belongs to the Salicaceae family within the Populus genus. Narrowleaf Cottonwood is native to western North America. Narrowleaf Cottonwood is also known as Mountain Cottonwood.

Narrowleaf Cottonwood displays a fast-growing deciduous tree growth habit, reaching up to 100 ft tall with a spread of approximately 50 ft. Narrowleaf Cottonwood produces inconspicuous flowers in drooping catkins.

Leaf size: approximately 6 inches.

Water a young or newly planted Narrowleaf Cottonwood every 7–14 days, soaking the whole root zone, until it is established — usually one to two growing seasons. Established trees mainly need water during long dry spells. In a container, water whenever the top few centimetres of soil are dry.

Narrowleaf Cottonwood thrives in full sun to partial shade.

Populus angustifolia tolerates temperatures of 50–100°F. Narrowleaf Cottonwood prefers humidity levels of 30–70%.

Moist, well-draining soil rich in organic matter. Good drainage is essential for Narrowleaf Cottonwood to prevent waterlogging, which leads to root rot and fungal issues.

Feed Narrowleaf Cottonwood every 12 months during the growing season with a balanced, slow-release fertilizer at the rate on the label. Established trees in good soil often need little extra feeding, so let weak growth or pale foliage guide you.

Stop feeding by late summer so new growth can harden before winter.

The PlantoScan app can remind you when to water and when to fertilize each plant.

Choose a spot with full sun to partial shade and moist, well-draining soil rich in organic matter. Avoid low spots where water collects after rain.

Narrowleaf Cottonwood is suited to USDA Zone 3a – 8b.

Plant container-grown or balled-and-burlapped trees in spring or early autumn, setting the root flare at soil level, and water well after planting.

Narrowleaf Cottonwood can spread to about 50 ft (15.2 m) and reach about 100 ft (30 m) tall. Space plants about 50 ft (15.2 m) apart so mature crowns don't crowd each other, and plant at least half that distance from buildings, fences and paths.

Planning a row or hedge? Try the tree spacing calculator.

Prune Narrowleaf Cottonwood while it is dormant in late winter: first remove dead, damaged and crossing branches, then thin lightly for shape.

If it flowers in spring, prune right after flowering instead so you don't remove next year's buds. Never take off more than about a quarter of the tree in one year.

Narrowleaf Cottonwood is hardy down to USDA zone 3a, so once established it can stay outdoors through winter in that zone and warmer ones.

Water deeply in late autumn before the ground freezes, and spread a 5–8 cm (2–3 in) layer of mulch over the root zone, keeping it away from the trunk.

Young and container-grown trees need extra protection: roots in a pot freeze much more easily than roots in the ground.

Narrowleaf Cottonwood can be propagated through seeds, hardwood cuttings. Similar propagation techniques also apply to quaking aspen plant care, which shares the same genus.

See all plants toxic to cats and plants toxic to dogs.

Narrowleaf Cottonwood is susceptible to aphids, caterpillars, leaf beetles. Inspect the foliage regularly, especially along leaf undersides and stems. Treat infestations promptly with insecticidal soap or neem oil to prevent spread.

Yellow leaves, brown tips or drooping? See common plant problems and how to fix them.

Narrowleaf Cottonwood grows outdoors in USDA Zone 3a – 8b. It survives winters down to planting zone 3a. Narrowleaf Cottonwood is native to western North America.