Would you like to get to the root of how to plant trees for Arbor Day? Here’s tree planting information from “The Colorado Gardener’s Companion: An Insider’s Guide to Gardening in the Centennial State.”
Pity the poor trees in our semi-arid region. Intense, high-altitude sunlight, extreme fluctuations in temperature, lean soil, and drying winds create a most inhospitable environment. Because trees have such a difficult time growing in Colorado, every day should be Arbor Day here.
Did you know the average life expectancy of a landscape tree is less than ten years because of where and how it’s planted?
Most often trees are planted too deeply. Other times they receive too much or too little water while getting established. Many times they’re left to fend for themselves.
The key to planting trees has to do with giving roots room to spread out. Without adequate rooting space, a tree’s growth will be limited. The root zone on a tree is like a wide, flat saucer. Roots are found in the top 12 to 18 inches of soil and spread out horizontally about 1 1/2 to 2 1/2 times the height of the tree.
When planting your Arbor Day tree, follow these steps to reduce transplant shock and encourage root growth:
- Dig a saucer-shaped planting hole that is at least three times the size of the root ball. The hole should be shallow (no deeper than the root-ball) and wide. Remember that planting too deeply restricts oxygen and slows root growth.
- Set the root ball on the undisturbed soil 1 to 2 inches above the soil grade.
- Make sure the trunk flare is visible; cover the rounded area of the root ball with backfill soil.
- Water and mulch over the root ball.
Keep in mind that trees need time to get established in the landscape. It takes about one year for every inch diameter of tree trunk to get the roots established. Be sure to care for newly-planted trees through the winter by watering when the weather is dry.