When you plant a tree, you want to ensure that it won’t lean or fall over so you should plant it deeply, right? Wrong! It may surprise you to learn that planting too deeply is one of the primary causes of premature tree death. Instead, trees should be planted so that the root flare at the base of the tree is above ground. Keep reading to find out why and how to properly plant a new tree at the right depth.
Planting a tree is an exciting endeavor that can add beauty, shade, and value to your property. However, in order to give your new tree its best chance at a long, healthy life, it’s important to plant it at the proper depth. This article will explain everything you need to know about how deep to dig when planting a tree.
Why Proper Planting Depth Matters
The depth at which you plant a tree sets the foundation for how well it will establish itself and grow. Plant too shallow and the roots won’t have enough room to anchor and supply the tree. Dig too deep and you risk damaging the root system. Improper planting depth can also lead to issues like
- Girdling roots
- Poor stability
- Drought stress
- Nutrient deficiencies
- Shortened lifespan
Taking the time to get the planting depth right will pay dividends for years to come in the form of a robust, thriving tree.
How Deep Should You Dig to Plant a Tree?
The ideal planting hole depth is 2-3 inches less than the height of the root ball or container This allows the root flare to sit slightly above ground level when planted
The root flare is where the tree’s roots spread out at the base of the trunk. It’s important that this area is partially exposed, as roots need access to oxygen. Burying the root flare can lead to root rot and other problems.
Step-by-Step Guide to Proper Planting Depth:
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Measure the height of the root ball or container. This is from the bottom to where the trunk flares out.
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Dig a hole 2-3 inches shallower than the root ball height. The bottom of the hole will support the root ball.
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Place the tree in the hole. The top of the root flare should be level with or slightly above the surrounding soil. If it’s lower, remove the tree, backfill, and re-dig to the proper depth.
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Backfill around the root ball with native soil. Tamp down gently to stabilize. Do not stomp or pack tightly.
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Water thoroughly after planting to settle the soil. Continue deep watering as the tree establishes over the next 2 years.
What Happens if the Hole is Too Shallow?
Planting too shallow is one of the most common mistakes when installing trees. Here are some of the problems it can cause:
- Exposed roots that dry out easily
- Poor anchoring that makes the tree unstable
- Surface roots that interfere with lawn care and hardscapes
- Drought stress due to limited water and nutrient absorption
- Slow growth and reduced health
- Shortened lifespan
Essentially, inadequate depth prevents proper root development and causes significant stress to the tree.
What if the Hole is Too Deep?
While too shallow is bad, too deep can also be problematic:
- Bark and root decay from lack of oxygen
- Girdling roots that strangle the tree
- Poor stability as anchoring roots are too high
- Drought stress since deep water-seeking roots don’t develop
- Nutrient deficiencies as key nutrients are near the surface
- Increased vulnerability to pests, disease, and other threats
- Premature death due to rot and root issues
Between rot, girdling roots, and stress, over-deep planting dramatically shortens the life expectancy of trees.
How Wide Should the Planting Hole Be?
While depth is critical, pay attention to width as well. A good guideline is to dig the hole 2-3 times wider than the root ball or container size. However, don’t go excessively wide, as this can cause slumping of loose backfill soil.
The broad hole encourages horizontal root growth, which is important for stability, access to water and nutrients, and overall tree health. Roots typically grow more outward than down.
Adjusting for Problem Soils
The proper planting hole dimensions described so far assume you’re planting in nutrient-rich, well-draining soil. However, many sites have less than ideal soil conditions such as:
- Poorly draining clay
- Sandy soil that drains too quickly
- Compacted soil that restricts roots
- Shallow bedrock or hardpan that limit depth
In these cases, you may need to make some adjustments:
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For drainage issues, plant a little higher, build a raised berm, or amend the backfill.
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For sandy or gravelly sites, incorporate organic matter in the backfill to retain moisture.
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For compacted or shallow soils, loosen more area around the hole for roots to spread.
Modifying your technique or materials can help overcome challenging soil conditions.
Key Takeaways on Planting Hole Depth
Follow these tips to ensure your new tree gets off to the right start:
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Measure root ball height and dig 2-3 inches shallower.
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Plant at the proper depth so the root flare is at or slightly above the surface.
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Make the hole 2-3 times wider than the root ball.
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Backfill with native soil, tamp gently.
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Water at planting and as the tree establishes.
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Adjust for problem soils with amendments or modifications.
Taking the time to plant at the proper depth will pay off for the lifespan of your tree. If you have any questions about the ideal planting hole depth, consult with a professional arborist.
With the right planting techniques, your new tree can grow to its full potential and provide beauty and enjoyment for years to come.
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Titan Tree Care is a full-service tree care company located in Anthem, AZ and serving all of North Phoenix. We offer a wide range of services to meet your tree care needs, including tree and palm trimming, tree pruning, tree removal, stump grinding, and more. We also offer insect or disease treatments and fertilization services. We are dedicated to providing high-quality, safe, and effective tree care services to our customers and work hard to ensure that your trees are healthy and look their best.
Why is the Root Flare Important When Planting a Tree?
Root flare, also called trunk flare, is extremely important to a tree’s health. The root flare is found at the base of the trunk where the tree’s trunk ends and the root system begins.
Often roots develop about 12 inches below the soil line, which is just below the tree flare. Root flare depth is important. Trunk tissue surrounding the root flare, the phloem, can rot if it receives too much moisture. Phloem is an important part of a tree because it helps in the manufacture of energy for foliage production. Burying the root flare or piling it high with mulch when planting a tree can encourage the rot of the phloem.
Proper Tree Planting Depth | From the Ground Up
FAQ
How deep should I dig a hole when planting a tree?
The hole sides should be slanted and the hole should be no deeper than the root ball is tall, so it can be placed directly on undisturbed soil. Tree roots typically grow more sideways than vertical and most roots stay fairly shallow, so a wide shallow hole fits the form of the root system.
How deep should a tree be buried?
Therefore, for proper planting hole depth, take the measurement of the root ball and subtract 1-2 inches to ensure your tree sits slightly above ground level.
How deep do you dig to transplant trees?
Using a spade, dig a trench around the tree to a depth of 1-1/2 to 2 feet. Then cut beneath the roots, rounding the bottom of the soil ball. Tip the soil ball to one side, place a piece of burlap in the trench on the opposite side, then carefully tip or roll the soil ball over onto the burlap.
How deep should a potted tree hole be?
The hole should be 2–3 times the width of the tree’s root ball. The hole should be somewhat shallow. 1–2 inches (2.5–5 cm) of the root ball should stand above the top of the hole. Periodically test the size of the hole as you dig by placing the potted tree inside. The hole you dig should not be excessively deep.
Can a tree be planted too deep?
Planting a tree too deeply can cause serious health issues. Make sure to remove any planting soil from the root flare and dig a hole that is no deeper than the length from the bottom of the root ball to the root flare.
How deep should a tree be planted?
With trees, an even better guide is to look for the flare of the trunk near the soil level. Don’t place the tree in the planting hole so deep that any part of that flair is covered with soil. The truth is, even nurseries sometimes put plants in containers too deeply.
How wide should a hole be when planting a tree?
When digging to plant a tree, it’s best to excavate a wide planting hole. The hole should be 2–3 times the width of the tree’s root ball. This loosens soil near the tree, allowing young roots to easily develop and spread, for better tree health. The hole should be 2–3 times the width of the tree’s root ball.
Should you dig a hole to plant a tree?
Planting a tree isn’t as simple as digging a hole and dropping the tree in. An improperly dug hole can cause a tree to struggle and die, or contribute to tree diseases. On the other hand, a properly dug hole makes tree cultivation a breeze. Get the job done right and you’ll have few worries with your tree in the future.
What if a hole is too deep for a tree?
If by chance, you place the tree in the new hole and discover that the hole is too deep, don’t despair. Simply remove the tree and shovel some dirt back into the hole. Pack the bottom of the hole tightly so the root ball won’t sag after the first rainfall. The hole width is just as critical as the tree planting depth.