Leyland cypress trees (Cupressus × leylandii) are a popular evergreen tree species widely used in landscaping and horticulture. The Monterey cypress (Cupressus macrocarpa) and Alaskan cedar (Chamaecyparis nootkatensis) bred with each other to make this hybrid species. People like Leyland cypress trees because they grow quickly, have dense foliage, and can be used to make a tall, dense screen or windbreak.
People love these trees for their thin, cone-shaped bodies and dark green leaves that stay bright all year. They are often used as privacy screens, windbreaks, or as ornamental trees in gardens and parks.
Growing Leyland cypress trees successfully involves choosing a sunny location with well-drained soil. First, dig a hole twice as wide as the root ball. Then, fill the hole back up with soil and water it well. Ensure regular watering and use organic mulch to retain moisture efficiently.
To maintain their health, prune Leyland cypress trees regularly, removing dead or overcrowded branches. Keep an eye out for pests and diseases and shield them from harsh weather conditions like drought and high winds to make sure they stay healthy and beautiful for a long time. Leyland cypress trees prefer well-drained soil and full sun but can tolerate a range of soil conditions. They are relatively low-maintenance and are used in urban landscapes due to their adaptability and aesthetic appeal. They can get some diseases and pests, though, so it’s important to take care of them and keep an eye on them to make sure they stay healthy and live a long time.
The Leyland cypress (x Cupressocyparis leylandii) is a popular evergreen tree known for its rapid growth and lush green foliage. One key factor that influences how these trees grow is their root system. Let’s take a closer look at the spread depth and other traits of Leyland cypress roots to better understand how to care for these trees.
An Overview of Leyland Cypress Roots
Leyland cypress trees have a relatively shallow, non-invasive root system compared to many other tree species The roots tend to grow wide but not deep. The spread of the root system is generally equal to the height of the tree So for a Leyland cypress growing to 40 feet tall, you can expect the roots to reach out 40 feet from the trunk.
Some key facts about Leyland cypress roots
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Root Depth: 12-24 inches deep typically
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Root Spread: Equal to tree height
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Root Structure: Fibrous, with no prominent taproot
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Root Invasiveness: Low; not prone to damage structures
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Drought Tolerance: Low, requires sufficient irrigation
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Close Planting: Possible since roots don’t intertwine
The Shallow Nature of the Roots
One defining characteristic of Leyland cypress trees is their shallow root system. Unlike trees like oaks that can grow roots 50 feet deep or more, the roots of a Leyland cypress generally only grow 12-24 inches below the soil surface. They tend to be spread over a large area but don’t extend far down into the earth.
This makes Leyland cypresses more prone to drought stress and wind damage than deep-rooted trees. Their roots can’t reach down to tap into deeper groundwater reserves. Regular irrigation is needed to keep their shallow roots hydrated. Mulching around the tree and careful planting techniques that encourage deep root growth are important.
The shallow roots also mean it’s critical not to plant Leyland cypresses too deep. The root flare where the roots meet the trunk should be partially visible above the soil line. Burying this root flare can lead to decline.
Widespread But Not Invasive Roots
While Leyland cypress roots are shallow, they make up for it by growing extensively in their search for water and nutrients. The root system can spread out a distance equal to the tree’s height, especially if planted in groups.
However, Leyland cypress roots are not considered invasive. They typically won’t cause damage by growing into sewer lines, sidewalks, or building foundations. The roots from multiple trees don’t tend to intertwine or graft together.
This means Leyland cypresses can be planted fairly close together in rows or groups to form screens and barriers. Just leave adequate space between trees—generally 10-15 feet—for good air circulation. Monitor for signs of disease which can spread more readily at close spacing.
No Taproot Structure
Most Leyland cypress trees lack a strong central taproot. Instead, they develop a fibrous root system composed of many small lateral roots spreading out horizontally with no distinct large vertical taproot.
This is one reason Leyland cypress trees depend on their widespread lateral roots for stability and moisture uptake. The extensive network of small fibrous roots efficiently absorbs water and nutrients from the surrounding soil.
Proper planting techniques can encourage deeper root growth. Score the sides of root balls before planting to promote roots growing outward into the native soil.
Caring for Leyland Cypress Root Systems
Now that we’ve explored the growth habit and characteristics of Leyland cypress roots, let’s look at some care guidelines to maintain their root health:
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Water thoroughly – Provide deep watering during dry periods to hydrate the shallow root zone.
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Mulch – Apply 2-4 inches of organic mulch over root areas to retain moisture.
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Avoid soil compaction – Don’t pile heavy materials near trees that could compact the soil over the shallow roots.
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Fertilize lightly – Use a balanced, slow-release fertilizer in early spring if needed based on soil tests.
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Watch for signs of stress – Drooping branches, yellowing foliage, and thinning canopy indicate roots are not getting adequate water and nutrients.
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Plant at proper depth – Don’t bury the root flare; leave it partially exposed when planting.
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Control weeds & grass – Competing plants steal water and nutrients from tree roots.
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Prune lower branches – Remove lowest branches to increase light and air getting to the root zone.
Maturity and Life Span of Roots
Leyland cypress trees grow incredibly quickly, adding 3 feet or more of height per year when young. Their root systems expand rapidly to support this fast top growth.
It takes about 15-20 years for Leyland cypress trees to reach maturity. At this point, the extensive root system is fully developed to anchor and support the 40-60 foot tall tree.
Mature Leyland cypress trees have a relatively short life span of just 25-50 years. Their shallow roots make them more vulnerable to decline and blowdown compared to long-lived trees with deep anchoring taproots.
Plan for the eventual removal and replacement of Leyland cypresses within a few decades of planting. Choose sites carefully since it’s difficult to transplant mature specimens.
Avoiding Root Problems
Some common issues to watch for with Leyland cypress roots include:
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Girdling roots – Roots that encircle the trunk can strangle trees as they grow. Watch for flattened trunks and slow growth.
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Root rot – Fungi can infect stressed roots in overly wet soils, causing decline. Improve drainage and avoid overwatering.
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Drought stress – Shallow roots dry out readily, seen as scorched brown foliage. Water thoroughly when dry.
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Compacted soil – Lack of oxygen from overly compacted clay or heavy foot traffic harms roots.
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Root competition – Grass and weeds steal water before tree roots can absorb it. Mulch and weed regularly.
Careful planting, irrigation, and protection of the root zone can help keep your Leyland cypress roots healthy and minimize these issues.
Key Takeaways on Leyland Cypress Roots
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Leyland cypresses have a shallow, non-invasive root system that spreads out widely but not deeply.
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The extensive surface roots efficiently absorb moisture and nutrients but also make trees prone to drought stress.
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No prominent taproot forms; instead the roots are finer and fibrous.
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Allow enough room between trees for root spread and air circulation.
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Monitor new plantings until the root system is well established.
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Avoid overwatering, soil compaction, and weed competition around root zones.
Understanding the root system habits of Leyland cypress trees allows you to provide the best care from planting through maturity. Ensuring healthy roots means your Leylands will grow vigorously and enhance your landscape for years to come.
How do you make Leyland cypress grow thicker?
Leyland cypress will grow thicker if you cut the central branches back shorter than the final height you want them to be. This will encourage the growth of dense foliage. This is repeated multiple times in one pruning season to create a dense and flat wall of foliage.
Aggressive Growth and Shallow Roots
One common complaint about Leyland cypress trees is their aggressive growth and accompanying shallow root system. These traits make the tree unstable, especially when the ground is wet, which causes it to fall over in strong winds.
To manage these characteristics of mature trees, yearly pruning is essential. Proper planting techniques prevent the trees from toppling over and manage their aggressive growth.
The branches of a tree start to wither, decline, and eventually die. This is called branch dieback. This process typically starts with the tips of branches and progresses inward towards the trunk. Branch dieback is caused by various factors, including environmental stressors, pests, diseases, (like Seiridium canker), or physical damage. Damage from diseases like Seiridium canker or snow and ice shows up as yellowing or browning leaves on branches and cankers, which causes twigs and branches to die back.
To prevent and treat this problem, make sure trees are spaced out correctly so air can flow, don’t fertilize too much, and water regularly. If you see branches turning brown and dying back, you need to cut them off right away because that means canker disease has started.
How Big Is a Leyland Cypress Root System?
FAQ
Do cypress roots grow down or out?
Can I plant a Leyland cypress close to my house?
How invasive are the roots of Leylandii?
Do Leyland cypress trees have deep roots?
Leyland cypress trees do not have deep roots; they have a shallow root system about 2 feet deep. The roots of the leyland cypress are pretty broad but not so deep. The width of the Leyland cypress tree depends on the height of the tree. In most cases, the roots spread more than half the tree’s height.
Does a Leyland cypress have a taproot?
The Leyland cypress does not have a main taproot. Its roots are small and very shallow, staying close to the surface of the soil, and they have a minimal spread, especially for such a large tree.
How does a Leyland cypress tree propagate?
The Leyland cypress tree does not occur naturally and must be propagated by root cuttings. It has a fairly poor root system and does not have a main taproot, making it unstable in bad weather. The roots are small and very shallow, staying close to the surface of the soil.
Does Leyland cypress spread?
Leyland cypress does not spread or multiply easily. It’s also quite hard to grow them with seeds. Leyland cypress does not also grow another plant from its root, like banana trees. So you don’t need to worry about spreading issues if you have Leyland cypress trees.
What is a Leyland cypress?
Garland & Gerry Moore The Leyland cypress, Cupressus × leylandii, × Cuprocyparis leylandii or × Cupressocyparis leylandii, often referred to simply as leylandii, is a fast-growing coniferous evergreen tree much used in horticulture, primarily for hedges and screens.
Can Leyland cypress grow in concrete?
The tap root is the central root that goes deep and stores food for difficult times. The shallow roots of the leyland cypress are harmless and do not penetrate any buildings. They also don’t become woody and thick enough to lift concrete slabs. But you should always keep 20 feet distance from the buildings if you want to plant a Leyland cypress.