- Leyland Cypress Tree: How To Grow Leyland Cypress Trees
- Information About Leyland Cypress
- How to Grow Leyland Cypress Trees
- Leyland Cypress Care
- Growing a Leyland Cypress Pruned Hedge
- The Origin of Leyland Cypress
- Pruning Leyland Cypress – Tips On How To Trim A Leyland Cypress Tree
- Leyland Cypress Pruning
- How to Trim a Leyland Cypress Tree
- Leyland Cypress
- Mature Height/Spread
- Growth Rate
- Ornamental Features
- Landscape Use
Leyland Cypress Tree: How To Grow Leyland Cypress Trees
Flat stems of feathery, blue-green foliage and ornamental bark combine to make Leyland cypress an appealing choice for medium to large landscapes. Leyland cypress trees grow three feet or more per year, making it an excellent choice for a quick specimen or lawn tree, or a privacy hedge. Information about Leyland cypress will help with growing healthy trees.
Information About Leyland Cypress
Leland cypress (x Cupressocyparis leylandii) is a rare, but successful, hybrid between two different genera: Cupressus and Chamaecyparis. Leyland cypress has a short lifespan for an evergreen tree, surviving for 10 to 20 years. This tall evergreen conifer is grown commercially in the Southeast as a Christmas tree.
The tree grows to a height of 50 to 70 feet, and although the spread is only 12 to 15 feet, it may overwhelm small, residential properties. Therefore, larger areas are most suitable for growing a Leyland cypress tree. The tree is also useful in coastal landscapes where it tolerates salt spray.
How to Grow Leyland Cypress Trees
Leyland cypress trees need a location in full sun or partial shade and a rich, well-drained soil. Avoid windy sites where the tree may be blown over.
Plant the tree so that the soil line on the tree is even with the surrounding soil in a hole about twice as wide as the root ball. Backfill the hole with the soil that you removed from it without amendments. Press down with your foot as you fill the hole to remove any air pockets that may be present.
Leyland Cypress Care
Leyland cypress trees need very little care. Water them deeply during prolonged drought, but avoid overwatering, which can lead to root rot.
The tree doesn’t need regular fertilization.
Watch for bagworms and, if possible, remove the bags before the larvae they contain have a chance to emerge.
Growing a Leyland Cypress Pruned Hedge
Its narrow, columnar growth pattern makes Leyland cypress ideal for use as a hedge to screen out unsightly views or protect your privacy. To form a pruned hedge, set out the trees with 3 feet of space between them.
When they reach a height about a foot beyond the desired height of the hedge, top them to about 6 inches below that height. Prune the shrubs every year in midsummer to maintain the height and shape the hedge. Pruning during damp weather, however, can lead to disease.
The Origin of Leyland Cypress
Although its popularity may be declining since its heyday in the last century, Leyland cypress is still widely planted by gardeners looking for quick hedges and privacy screens. Often they end up with more than they bargained for, right down to legal disputes with neighbours and their city. While much safer for drains and foundations than many other more widely loved trees, and a top-rate screen from a highway, it has a reputation for easily growing out of bounds. Smart gardeners with small gardens should probably avoid it, unless they love trimming hedges.
As controversial as it is, the history of this tree is an insight into the past, and just one of the many fascinating stories about where our plants came from. We plant so many different trees, but we rarely think about their origins – maybe we think they just grow on trees. You will not find the majority of the plants we grow in our gardens out in the natural world. They are often the product of complex and skilled breeding programs stretching over decades, but they are just as often the result of pure serendipity, which is how we came to have the Leyland cypress.
In the affluent and relatively calm period that went from the middle of the 19th century to World War I, gardening was a popular pursuit of the wealthy classes on both sides of the Atlantic, but especially in the UK. It was a time when the owners of grand estates vied with each other to show off the latest arrivals from around the world, and laced their teatime conversations with Latin names and botanical speculations. John Naylor was certainly a member of that privilege class, living at Leighton Hall, just across the English border in Wales. The estate dated back to 1541, and in 1845 Christopher Leyland, a wealthy banker, had bought it. Two years later, he gave it as a wedding present to his favorite nephew, John.
The first task was to rebuild the house, which he did at a cost of £275,000 (perhaps $40 million today). For the grounds he hired the landscape designer Edward Kemp. Still a young man, Kemp was at the start of an illustrious career that would put him on a par with the more famous Joseph Paxton as a designer in the English Landscape Style. Trees were a critical element in that style, and Kemp made sure to include a wide variety of them, from around the world. The extensive grounds became an arboretum of the rare and exotic.
The One in a Million Cone
Among those trees was Nootka cypress, Cupressus nootkatensis, a tree widespread along the Pacific Northwest coast of North America. This forest tree grows from the Siskyou Mountains in northern California all the way to Prince William Sound in Alaska. In 1888, while walking around his estate, John Naylor picked a cone from one of these trees and had his gardeners grow some of the seeds for him. Perhaps he simply wanted to have a few more of these handsome trees on his grounds.
When John died, one of his three sons, Christopher John, inherited Leighton Hall. A few years later, in 1891, Christopher also inherited the estates of an uncle, Thomas Leyland. The major part was Haggerston Castle, on 23,000 acres near the border with Scotland. As was typical of complex inheritances, this caused Leighton Hall to pass to a younger brother of John Naylor, and Christopher took his uncle’s name, becoming Christopher Leyland.
An ambitious gardener with a keen interest in trees, Christopher developed Haggerston Castle into a grand rival for his father’s property, and during the move took with him six of those cypress seedlings to plant on his new grounds.
In 1911, back at Leighton Hall, another nephew was to repeat the random act of John Naylor by also picking up a cone, but this time from a Monterey cypress growing just 150 feet from that original Nootka cypress. Monterey cypress, Cupressus microcarpa, today grows wild only in two small areas on the coast of California, both of them nature reserves.
Christopher Leyland noticed that two of his seedlings were remarkably vigorous and he called one ‘Haggerston Grey’ and the other ‘Green Spire’. The best two trees from that second cone were called ‘Leighton Green’ and ‘Naylor’s Blue’.
The Botanists Get to Work
At this point, the botanists join the story. In 1925 a Cambridge professor, William Dawson, was a house guest at Haggeston Castle. Leyland had already noticed the virtues of his seedlings, chiefly in their rapid growth and resistance to salt-spray from the ocean nearby. He asked Dawson to take some samples to William Dallimore, the conifer expert of the time. Dallimore had worked his way up from a humble student gardener at the Royal Botanic Gardens, Kew, to become an authority, and his recent book, Handbook of Coniferae and Ginkgoaceae, was considered the definitive work. He pored over the specimens and pronounced them to be hybrids between the Nootka and Monterey Cypresses. Dallimore and his associate Jackson published their findings in the Kew Bulletin of March, 1926, and named the tree Cupressus x leylandii, in honor of Christopher Leyland. Cuttings were rooted and planted at several botanic gardens. One of the original trees was now 35 feet tall, and by 1930, it is listed in the catalogue of the famous Hilliers Nursery. Almost all plants in gardens derive from the ‘Haggerston Grey’ plant, which despite its name is of course green.
Five of the original six trees still survive exactly where they were first planted, but Haggerston Castle does not. Mr. Leyland died the same year he achieved immortality in the name of his tree, and the castle was demolished. Leighton Hall still survives, although today it is unoccupied.
Soon popular in Britain for hedging, the first plants crossed the Atlantic in 1941, when rooted cuttings arrived at the Institute of Forest Genetics at Placerville, California. From there trees went to the Strybing Arboretum in San Francisco and to the University of Washington Arboretum in Seattle. In 1953, Leyland cypress arrived in the east at the U.S. National Arboretum. In the 1960s, Clemson University in South Carolina distributed plants widely to southern nurseries, and the tree became even more popular than it was in Europe. The spread of suburbia, and the new mass-need for instant privacy between homes was a marketing opportunity nurseries across America and Europe were quick to grasp, and millions upon millions of plants were sold during the heyday of Leyland cypress.
In recent decades the tree has fallen out of favor, and has been widely replaced with the slightly less aggressive Thuja ‘Green Giant’, another chance hybrid, this time between Japanese Thuja (Thuja standishi) and Western Redcedar (Thuja plicata). Curiously, recent research into the genetics of cypress suggests that Monterey cypress is closely related to a rare Asian species and much more genetically distinct from Nootka cypress than was originally realized. A number of experts have moved it, and its Vietnamese relative, to the genus Xanthocyparis.
Based on this new information, Leyland’s tree is probably more correctly called x Cupressocyparis leylandii. Mr. Leyland’s miracle cypress turns out to be more like ‘Green Giant’ than thought, and these two trans-Pacific meetings of gene pools both bestow remarkable hybrid vigor on their famous offspring.
Pruning Leyland Cypress – Tips On How To Trim A Leyland Cypress Tree
Leyland Cypress (x Cupressocyparis leylandii) is a large, fast-growing, evergreen conifer that can easily reach 60-80 feet (18-24 m.) in height and 20 feet (6 m.) wide. It has a natural pyramidal shape and elegant, dark green, fine-textured foliage. When they become too large or unsightly, trimming Leyland Cypress trees becomes necessary.
Leyland Cypress Pruning
Leyland Cypress is often used as a quick screen because it can grow up to 4 feet (1 m.) per year. It makes an excellent windbreak or property boundary border. Because it is so large, it can quickly outgrow its space. For this reason, the native East Coast specimen looks best on large lots where it is allowed to maintain
its natural form and size.
Since Leyland Cypress grows so wide, do not plant them too close together. Space them at least 8 feet (2.5 m.) apart. Otherwise, the overlapping, scraping branches can wound the plant and, therefore, leave an opening for disease and pests.
In addition to proper location and spacing, pruning Leyland Cypress is occasionally needed – especially if you don’t have enough room or if it’s outgrown the allotted space.
How to Trim a Leyland Cypress Tree
Pruning Leyland Cypress into a formal hedge is a common practice. The tree can take severe pruning and trimming. If you are wondering when to prune Leyland Cypress, then summer is your best time frame.
During the first year, trim the top and sides to start forming the shape you desire. During the second and third year, trim just the side branches that have wandered out too far to maintain and encourage foliage density.
Leyland Cypress pruning changes once the tree reaches the desired height. At that point, annually trim the top six to twelve inches (15-30 cm.) below the desired height. When it regrows, it will fill in more thickly.
Note: Take heed where you cut. If you cut into bare brown branches, the green leaves will not regenerate.
Q: I heard you say on your radio show that Leyland cypress can be pruned way back. Mine were planted in 1991 when they were two feet tall. Now they have kind of got away from me. Is there anything that can be done with Leylands this huge or do I need to cut them down and start all over? It will pain me greatly to cut them down as numerous birds live in them.
A: It is true that a Leyland cypress can be topped to keep it at a certain height…but you can’t reduce it in size width-wise. This is because Leyland cypress does not sprout new growth from mature brown branches, like a holly or other broad-leafed evergreen would.
It MIGHT be possible to do some corrective pruning on your two huge trees but it all depends on how many short green branches are growing from the main trunk. If you have green needles only at the ends of the branches, cutting them off will leave only a trunk covered in lifeless limbs. This is likely to be your situation.
My advice? Put up several bird houses and cut down the cypresses. You can choose among several other needled evergreens to plant in their place. But DO read the labels of the new plants to learn how big they eventually will grow!
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Leyland cypress screening a parking lot.
Karen Russ, ©2007 HGIC, Clemson Extension
Leyland cypress (x Cupressocyparis leylandii) is a large, handsome evergreen that is used extensively in the Southeast. It is a favorite because it is fast growing. It is adapted to all of South Carolina.
This tree will grow 60 to 70 feet tall and 12 to 20 feet wide. Heights of 70 to 100 feet are not uncommon.
It grows rapidly when young (3 to 4 feet per year).
The Leyland cypress forms a graceful pyramid, with dense pendulous branches and fine, feathery foliage. This foliage, on flattened branchlets, is dark green or blue-green and is small and scale-like. The fruit (cone) is small and brown, and creates no litter problems.
This is a fast-growing evergreen when young and will quickly outgrow its space in small landscapes. It is an excellent choice for quick screens, hedges and groupings, especially on large properties. This tree tolerates severe trimming, and can be restrained at an early age with pruning. Although Leyland cypress can be sheared into a tall screen on small lots, it is most effective when allowed to develop into its natural shape. Regular trimming is necessary to retain a formal hedge, screen or windbreak. When considering this tree for use in a design, be mindful of its projected height. It usually grows larger than most people desire. It is a good background plant, and contrasts well with broadleaf evergreens.
This tree prefers sun to part shade and well-drained fertile soil. It is very adaptable, however, and tolerates acidic or alkaline soils and poor drainage on occasion. It withstands salt spray and is suited for coastal landscapes. Prune only during dry periods to help prevent disease.
The most serious problem is a canker that causes branch dieback to the main trunk, and can seriously disfigure or kill the tree. To help prevent spread of this fungus, spray with a fungicide, and prune only during dry periods. Bagworms can also be a major insect problem on this tree. For further information on problems on Leyland cypress, refer to the fact sheet HGIC 2004, Leyland Cypress Diseases & Insect Pests.
- ‘Castlewellan’- This is a somewhat compact form. It has gold-tipped foliage, which is more pronounced in fall, winter and spring.
- ‘Leighton Green’- This tree is tall and columnar, with dense branching and dark green foliage.
- ‘Haggerston Gray’ – This tree has irregular lateral branches with sage green foliage.
- ‘Naylor’s Blue’ – This columnar form is more loosely branched and open than most. The foliage is blue-gray. It may be slower growing.
- ‘Silver Dust’ – This wide-spreading form has blue-green foliage marked with variegation.
- ‘Greenspire’ – This narrow, columnar form has very dense, rich green foliage.
Note: Chemical control of diseases and insects on large trees is usually not feasible since adequate coverage of the foliage with a pesticide cannot be achieved.