Poplar, Aspen, or Cottonwood
Populus species (SALICACEAE)
Planting and Growing Poplar Trees
You’ll find everything you need to know to plant and grow poplar, aspen, or cottonwood trees in the accompanying table’s tabs:
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- Foliage, catkins, and seeds of poplar, aspen, or cottonwood
- Growing conditions for poplar, aspen, or cottonwood
- When to plant poplar, aspen, or cottonwood
- How to plant poplar, aspen, or cottonwood
- How to prune poplar, aspen, or cottonwood
- Watering, fertilizing, and care of poplar, aspen, or cottonwood
- Landscape uses of poplar, aspen, or cottonwood
- Pest and disease control for poplar, aspen, or cottonwood
Growing Poplar Trees
Nearly 40 species of fast-growing, short-lived, upright, columnar or branching, open, deciduous trees, varying in height depending on the species, with shiny, light green, heart-shaped, pointed, toothed leaves, 2–5 in. (50–125 mm) long, sometimes with light green, silver undersides, turning gold, red, yellow in autumn, and with gray, gray green, white, rough, furrowed bark.
Poplar Planting and Care Guide
Bloom and Seed
Willowlike catkins, to 2 in. (50 mm) long, in early spring before leaves emerge, form brown, clustered, hairy seed, 1/2–1 in. (12–25 mm) long, in spring.
Best Climates
U.S.D.A. Plant Hardiness Zones 2–9, depending on species.
Soil Type and Fertility
Moist, well-drained soil. Fertility: Rich–average. 5.5–7.0 pH.
Where and How to Plant
Full sun. Space as recommended for species.
Proper Care
Moderate. Keep evenly moist. Avoid fertilizing. Prune in autumn to shape, remove suckers. Propagate by cuttings, grafting, seed, suckers.
About This Species
Good choice for borders, fencelines, groups, screens in cold-climate, mountain gardens. Good for temporary plantings. Drops leaves, seed, twigs, requiring maintenance. Very invasive. Shallow rooted. Generally disease resistant. Cottonwood leaf beetle, poplar curculio, scale susceptible.
Common Species and Varieties of Poplar
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- Populus X acuminata, lance-leaved cottonwood
- Populus alba, white poplar
- Populus angustifolia, narrow-leaved poplar
- Populus balsamafera, balsam poplar
- Populus X berolinensis, Berlin poplar
- Populus X canadensis, Carolina poplar
- Populus canescens, big-leaved poplar
- Populus deltoides, eastern poplar
- Populus fremontii, western cottonwood
- Populus grandidentata, large-toothed aspen
- Populus lasiocarpa, Chinese poplar
- Populus maximowiczii, Japanese poplar
- Populus nigra ‘Italica’, Lombardy poplar
- Populus simonii, Simon poplar
- Populus tremuloides, quaking aspen
- Populus trichocarpa, black cottonwood
About Poplar Trees
The Populus genus includes between 30 and 40 species of erect, slim, broad-leaved, deciduous trees, from as small as 15–20 ft. (4.5–6 m) tall and to as large as 100 ft. (30 m). They are native to the northern hemisphere. All are hardy and grow best in cold-winter, mild-summer areas that experience winter chill below 20°F (–7°C) for several months.
Poplars are prized for their narrow or round-crowned form and their graceful foliage, which colors to gold, red, and yellow in autumn. Because they are fast-growing and short-lived, their best use is as a temporary filler or accent.
Keep in mind that aspen and poplar are shallow-rooted trees that tend to be invasive.
While they are moderately pest and disease resistant while young, they quickly become susceptible to beetle, poplar curculio, and scale as they mature and their growth slows. Also plan for frequent rakings to remove their fallen catkins, leaves, seed, and twigs.
Aspens, cottonwoods, and poplars are often featured in landscapes found in cold-winter climates, along creeks and rivers, or where soils are naturally moist.
Because poplar species are so varied, consider choices beyond the ones listed at left. Consult your garden retailer’s staff for advice on the best poplar species to plant in your region.Choose from among the popularly cultivated species above, at left.
Planting and Caring for Poplars
Poplars, aspens and cottonwoods are broad-leaved and deciduous, with attractive, heart-shaped leaves and open crowns. Because their wood is weak and branches sometimes fail at the crotch, they should be planted away from structures.
Plant poplars in moderately rich, moist, well-drained, acidic soil. All landscape trees grow best if planted in unamended soil; test the acid-alkaline balance of your site before you plant. Poplars should have soils in the 5.5–7.0 pH range. Choose those species that fit your climate and site.
When planting poplars, carefully match the depth of the planting hole to the soil line on the rootball of your tree. They do best when planted with their roots at the same depth below ground as they were grown at the nursery.
Backfill around the rootball with native soil and give the tree ample water, keeping the soil evenly moist until the tree becomes established. Avoid applying fertilizer as you plant poplars.
Care needs for poplars include regular raking of fallen catkinlike flowers, leaves, twigs, and winged seed.
Large poplars are good for seasonal shade above mixed-shrub borders, while those with smaller, more delicate forms are good landscape accents. In small-space gardens, the smaller species also make good container plants for use on balconies, decks, and patios. Be sure to regularly water all container trees.