This species is native to east Asia and is also commonly known as the Chinese elm. It is often confused with the Siberian elm (Ulmus pumila), but they are entirely different species and the Siberian elm is an inferior and invasive tree. While the lacebark elm has attractive fall color, its spring and summer color is not overly impressive, and its blooms are not stellar. What sets this tree apart, and where it gets its common name from, is the interesting exfoliating light and grey bark patterns it produces. It is usually found casting some shade as a specimen tree or lining a street or drive as it can tolerate a good amount of urban pollution. Another traditional use for the Ulmus parvifolia is as a deciduous bonsai, but it is one best reserved for experienced bonsai enthusiasts only. Although it is unique and adaptable, one flaw with the lacebark elm is the tendency for the species’ wood to break under high winds or ice load. However, this concern can be negated with early structural maintenance. The only ongoing maintenance that the species requires is some structural pruning to avoid breakage due to weather.
Light
Lacebark elms appreciate full sun. While they enjoy six hours of direct light daily, they can tolerate partial shade without any negative effects. Generally, however, the more sun the tree gets the better foliage color you can expect in the fall.
Soil
While lacebark elms are very adaptable when it comes to their soil, as long as the soil is moist and well-drained, it will not tolerate wet saturated soil for long periods. They are very adaptable in terms of soil pH.
Water
When initially planted, the lacebark elm needs to be watered weekly to ensure the roots establish themselves. It is important to remember that less frequent, deeper watering is preferable to frequent, light irrigation. Once the tree is established, there is no real need to continue with supplemental watering. The species has a good tolerance for droughts.
Temperature and Humidity
The lacebark elm is tolerant of a good range of temperatures that cover much of the United States. It thrives in USDA zones 5-9. It does have issues withstanding ice breakage and high winds, which needs to be considered when placing the tree in a landscape and determining its usage.
Fertilizer
On initial planting, root growth can be boosted by adding compost, but further fertilization is not needed unless growth is slow or stunted. When fertilizing a lacebark elm due to slow or stunted growth, performing a soil test to see the proper fertilizer formulation is the best idea. Using a nitrogen fertilizer that is slow release is recommended to prevent weak growth.
Pruning
Maintaining a lacebark elm during storms and winter months requires that proper preliminary maintenance must be carried out. During planting, staking should be performed on the tree to allow upright growth perpendicular to the ground; a 90o angle is what is trying to be maintained. Training the tree with structural pruning to establish a single leader is the next vital step. Then pruning to eliminate any deep V-shaped intersections and inner-pointing interior branches is the next order of business. Maintaining this schedule annually for the first few years will keep the tree structurally sound for some time into the future.
