Lombardy poplars are fast-growing trees, growing as much as 6 feet per year. They are known for their columnar form and unusual branching structure—the branches start close to the ground and grow upward, parallel to the trunk. In addition to being planted as privacy screens, they have been used to line golf courses.
The foliage turns yellow in the fall. As the tree ages, the bark blackens and develops furrows. Lombardy poplar trees are usually planted in the spring or fall.
|Common Name||Lombardy poplar|
|Botanical Name||Populus nigra 'Italica'|
|Mature Size||40-50 ft. tall, 10-15 ft. wide|
|Soil Type||Sandy, loamy|
|Hardiness Zones||3-9 (USDA)|
Lombardy Poplar Trees Care
A Lombardy polar tree is a popular choice when you want "living wall" privacy screens or windbreaks in a hurry. It comes at a price though; you can expect a lot of maintenance with this tree, Nurseries often sell only the male trees so you won't have cottony seeds blowing around. However, the problem with male trees is that they produce abundant pollen, which can be allergenic.
As this tree has shallow, spreading roots, you should plant it away from pipes, septic tanks, lawns, gardens, sidewalks, streets, and foundations.
Grow Lombardy poplar trees in full sun.
Lombardy poplars will do well in soil that is sandy, loamy, or very loamy. It should be well-drained.
This tree has medium water needs. About 1 inch of water every two weeks through rainfall or irrigation will suffice.
Temperature and Humidity
The Lombardy poplar can be grown in a wide variety of temperate climates, including those where the winter low temperature is far below zero. In hot and humid climates, this tree is even more susceptible to Cytospora canker.
Unless the soil is very poor, the tree usually grows vigorously without any fertilizer.
Other Types of Poplar Trees
Lombardy poplar trees are not the best choice if you want to plant a long-lived, healthy tree. Consider these fast-growing North American poplar species as an alternative:
- Quaking aspen (Populus tremuloides) , growing to a mature height of 50 feet, this is a relatively small tree, with leaves that tremble in a breeze
- Balsam poplar (Populus balsamifera), a very hardy tree reaching 50 to 80 feet in height
- Eastern cottonwood (Populus deltoides), a vase-shaped tree that is one of the largest eastern hardwood trees
Pruning Lombardy Poplar Trees
Little pruning is needed, as the tree will develop its own structure readily. The wood itself is weak and you can expect frequent limb breakage. You have to be careful when working around the trees because the bark is thin and easily damaged.
Propagating Lombardy Poplar Trees
It's rare that you would want to propagate a Lombardy poplar, but if you are so inclined, it can be done by rooting a hardwood cutting:
- In the late spring, take a 6-inch long cutting from a stem segment about 1/4 inch in diameter, making the cut about 1/8 inch below a pair of leaves. Pull off all the leaves on the lower half of the cutting, leaving 4 or 5 leaves at the top.
- Bury the bare end of the cutting into a 6-inch pot filled with a mixture of perlite and coarse sand. Water the pot and pack the mix tightly around the cutting.
- Place the pot in a shaded outdoor location and mist it several times a day to keep the leaves moist. Water the pot whenever the potting mix feels dry.
- After about two weeks, the cutting should be rooted; transplant it into a 6-inch pot and continue growing in a dappled shade location for two or three months until plentiful new growth is present. The sapling can be transplanted into a permanent garden location in the fall.
Growing Lombardy Poplar Trees from Seed
Propagation of the tree is typically done from hardwood cuttings and not from seeds, which are not commonly available.
Potting and Repotting
Because of its vigorous and fast growth, Lombardy poplar is not suitable for container growing.
The tree is hardy to USDA zone 3 and does not need any winter protection.
Common Pests & Plant Diseases
These trees are susceptible to borers, Cytospora canker, and bacterial wet wood, reducing their lifespan. Almost all of these trees develop stem canker disease by the time they are 15 years old. Long before they die, they may be disfigured by these pests and diseases, rendering them unattractive as landscape plants and necessitating their removal.
Common Problems with Lombardy Poplar Trees
Lombardy poplars are short-lived, often succumbing within 15 years to a number of pests and diseases. For that reason they are best planted as a temporary solution in combination with a row of longer-lived screening plants such as Colorado blue spruce trees or arborvitae trees.
Removing the trees after they have served their purpose, however, can be problematic because they have an extensive, aggressively growing root system and they keep sending out suckers from their stumps even after they have been cut down.
How far apart do you plant Lombardy poplars?
To serve as a privacy screen, Lombardy poplars are planted in a row and spaced about 8 feet apart.
Are Lombardy poplar trees messy?
The tree drops lots of leaves and twigs that will need to be cleaned up regularly, in addition to the masses of cottony seeds from female trees.
Are the roots of Lombardy poplar invasive?
They are highly invasive and can spread out two to three times the height of the tree if not contained. To minimize their spread, dig a planting trench for them and line its sides with a 40-mil, high-impact polyurethane barrier.