
Spring Tree Tips from Chicago Gateway Green: A well maintained, beautiful tree is its own reward, and with the proper care its benefits can continue for years to come.
Trees mitigate climate change by reducing urban heat islands and energy used to heat and cool buildings. They also lower ambient air temperatures and improve overall air quality, provide important habitat for urban wildlife, while further absorbing rainfall and lessening stormwater runoff, which in turn lowers pumping and filtration costs.
Studies also show that trees contribute to a sense of calm and promote psychological well-being. Tree-lined shopping districts are generally more popular and profitable than areas where trees are lacking. Trees also can increase the value of public and private property. Most importantly, trees absorb carbon and provide oxygen that is essential for all of life. It is estimated that two mature trees can provide enough oxygen for a family of four each year.
First Steps
For both homeowners and professionals, the first few steps in planting a new tree can potentially enhance or deter the proper growth of the tree. “What, Where and How to plant” are some of the most common planting questions. Purchasing locally grown trees is advisable, as they have already acclimated to the area’s weather and typical soil conditions. If you are buying a cultivar confirm whether it is disease and insect resistant. Be sure to also know the sun and shade requirements so that the right tree can be planted in right place to insure optimum growth and health.
Preparing for a Tree
When planting new trees there are many elements to consider to provide the optimum conditions for your trees survival. Implementing these best practices will help your tree to flourish.

One of the most significant mistakes is to plant the tree too deeply. Most trees roots are located in the top 12” of soil and if the roots are covered with more soil, the chance for oxygen exchange is compromised and cause the roots to suffocate. Planting a portion of the root ball slightly above grade and sloping the soil away from the trunk will help to ensure good trunk and root aeration.
Give yourself a head start by choosing trees that are hardy to your area and proven winners in the Upper Midwest: Chicago is in USDA zone 5 (-20°). See the Illinois Dept. of Agriculture’s comprehensive list of site specific trees. (Click on ”Reforestation” from the column on its left.)
Prepare the planting site:
- The planting hole should be 2 to 3 times wider than the root ball/container.
- Don’t dig the hole any deeper than the depth of the root ball/container.

Plant a portion of the root ball slightly above grade.
Different Tree Installations
Planting tips for trees in containers:
- Center the tree in the planting hole. Keep it straight with the branches pointing in the direction you want them to grow.
- Remove the tree from the container and remove dead or injured roots using sharp pruners.
- Backfill the planting hole, gently filling around roots.
- Water well. A rule of thumb is 1 inch of water per week during the growing season, either by gentle rainfall or watering.
- Avoid fertilizing until the root system is established.
- Place a 2” to 4″ layer of composted organic mulch (wood chips, leaves, etc.) around the tree. Keep mulch 1” to 2” back from the trunk.
Planting tips for balled & burlapped trees:
- Set ball on firmly packed soil to prevent settling
- Cut burlap and rope away from top third of root ball
- Once the tree is in place, remove twine and cut away as much burlap as possible. If the tree is in a wire basket, remove as much wire as possible. Center the tree, and gently backfill the planting hole, using water to settle soil around the root ball. Avoid fertilizer, as noted above.
- When staking is necessary, use two opposing, flexible ties.

Cut away rope and burlap.
Tree Care: Four Essential Elements
Most newly transplanted trees experience some level of transplant shock. Transplant shock causes a great deal of stress on the tree as it is tries to establish. Approximately one year of recovery is needed for every inch of tree diameter. Starting a regular tree maintenance and inspection program to head-off problems early, and providing good after-care will help maintain the health and vigor of your newly planted tree.
Watering
Proper watering is the single most important maintenance factor in the care of new trees. Since a newly transplanted tree has not extended its roots into the existing soil, adequate moisture needs to reach the root ball. Soil type and the amount of rainfall govern the amount of watering necessary. Too much or too little water can result in tree injury. More trees are killed by too much water than by too little. Newly planted trees may need to be watered regularly for 2-3 years until their root systems become established. Large trees may take longer.
For the first few months of the growing season after a tree is planted, the tree draws most of its moisture from the root ball. The root ball can dry out in only a day or two, while surrounding soil remains moist. On most well drained soil, one inch of water per week throughout summer and fall is required to establish and maintain good growth. In sandy soils, as much as two inches of water per week is needed. To water the root ball and surrounding area, let the hose run slowly at the base of the tree or use a root-watering needle under low pressure for 5-10 minutes.
Mulching
Mulch is another important element in good tree health care maintenance. Apply a 3-to-4-inch layer of organic, composted mulch (wood chips, leaves, or pine bark) extending from the base of the tree out past the drip line (end of the branches). Do not let the mulch rest against the trunk of the tree. All trees benefit from mulch, because, as the mulch breaks down, it provides an excellent growing medium for roots, and acts as a slow release fertilizer. Mulch will also help conserve moisture, moderate soil temperatures, eliminate weeds, and protect the trunk from mechanical injury, especially weed whips and lawn mowers.

Apply 3"-4" of mulch, but do not let mulch rest against the trunk of the tree.
Fertilizing
Fertilization at the time of planting is generally not recommended. This element of care is ineffective until the root system has a chance to reestablish. It is usually advisable to wait two or three years before applying fertilizer, and then it is recommended to get a soil test first (but only when the soil temperatures are at least 50 degrees). The test will measure the soil’s pH and the amount of organic matter present. If you amend the soil with organic matter before the tree is planted, then it should be incorporated into the entire planting area (not just the hole) before the tree is planted, and to a depth of one foot. This organic matter could be composed of chopped up leaf litter, well-aged manure, and rich compost. Refrain from adding peat moss as it can be a detriment especially when the existing soil drainage is poor.
Pruning
Pruning and staking are another important element of good after-care. Pruning after planting should be limited to removing dead, rubbing, or broken branches only. Wait at least a year before removing any larger limbs or shaping the structure of the tree or shrub. Remember, pruning encourages growth, so cut only where you need growth, and try to maintain the natural shape of the tree.
Occasionally trees may require support, especially in windy sites, to prevent uprooting and leaning until the roots have had a chance to grow and stabilize that tree. Avoid staking too rigidly. Some trunk flexibility allows the flare at the base of the tree to develop naturally. Inspect staking material regularly for tightness and damage, and remove after one or two years.
The following links may also be helpful:
To find out more about getting involved in a large-scale tree planting initiative that transforms vacant land into tree-filled green spaces, CGG’s Tree Partnership Program, visit Chicago Gateway Green’s web site at http://www.gatewaygreen.org/programs/tree-partnership/
As government budgets tighten, fewer trees will be planted by the City of Chicago and other public agencies making the good work of Chicago Gateway Green essential to expanding and maintaining our urban forest canopy. Learn more about Chicago’s Urban Forest and planting activities .