One of the most common tree-planting mistakes happens before the tree even goes in the ground: digging the hole too deep. It can cause a tree to slowly suffocate and decline, even years later.
Early spring is a great time to plant a tree. The soil is workable, temperatures are mild, and gardeners are eager to get new plants established. But planting a tree just a few inches too deep can waste both time and money.
Many people assume a deeply planted tree will be more stable. In reality, burying the root flare—the spot where the trunk widens and transitions into roots—can cause serious problems. The root flare should always sit at or slightly above the soil line. When it’s buried, moisture and soil stay pressed against the trunk, which can lead to rot and disease. Trees planted too deep often just don’t thrive.
How to Avoid Planting a Tree Too Deep
1. Dig the right hole.
Dig a hole that’s about twice as wide as the root ball, but no deeper. In poorly draining soil, the root ball should sit slightly above the surrounding soil level.
2. Prepare the root ball.
Carefully remove the tree from its pot or any synthetic wrapping, making sure the root ball stays intact. If the roots are tightly circling the root ball, cut the outer roots in two to four places from top to bottom to encourage them to spread outward.
3. Set the correct depth.
Lower the tree into the hole by holding the root ball—not the trunk. If the tree sits too low, add soil beneath it until the root flare is visible at or slightly above the soil surface.
4. Backfill and water.
Fill the hole about two-thirds full with the native soil you removed. Water thoroughly and gently press the soil to remove air pockets.
5. Finish planting and mulch.
Straighten the tree if needed, fill in the remaining soil, and create a small ring of soil around the hole to form a watering basin. Water again and add mulch, keeping it away from the trunk so the root flare remains exposed.
It’s a simple detail, but planting depth can determine whether a tree struggles for years or thrives for decades.
