Espaliering Trees
What are Espaliers?
Espalier (pronounced esp-PAL-yer) is an ancient horticultural practice of controlling woody plant growth to encourage increased fruit production, by pruning and tying branches to a frame. Plants are frequently shaped in formal patterns, flat against a structure such as a wall, fence, or trellis. It also refers to plants that have been shaped in this way.
There are indications that the concept of training trees flat against a wall goes back as far as the early Egyptians (the tomb of Amenhotep II from about 1400 BCE has paintings of espaliered fig trees). However many believe the technique originated with the Romans. During the Middle Ages in Europe, monastery gardens or castle courtyards often contained espaliered fruit trees. By the 18th century, espaliers reached their peak in Europe, especially in France and England. Royalty and commoners found that it helped them to grow fruits from temperate climates, such as peaches and figs. Some of the best examples are at the Versailles kitchen garden (Potager du Roi) designed by Jean-Baptiste de la Quintinie for Louis XIV.
Benefits of espaliers
Space - espaliered trees take up less space than ordinary trees. For those on smaller, urban sections this means you can grow more varieties of fruit than would otherwise be possible.
Production - by pruning and training the branches, the tree's energy is directed away from vigorous vertical growth into the shorter, lateral fruit-bearing spurs, resulting in heavier yields than on ordinary trees.
Pest control - the flat shape of espaliers make it easier to net or spray trees. Having at least 20 cm between the tree and a wall allows for air movement around the tree, helping control fungal diseases.
Sunlight - fruit ripening is improved as all fruit on the tree receive equal amounts of sunshine
Microclimate - trees can be positioned near north or west-facing walls to take advantage of your microclimates, encouraging those less cold-hardy trees to be more productive.
Harvesting - espaliered trees tend to be shorter than standard trees, meaning that fruit is generally within easy reach. Ripe fruit is more visible.
What can you espalier?
Apple and pear are traditionally used because their fruiting spurs can produce fruit for many years and the branches are quite pliable when the trees are young, allowing you to train them into the espalier shapes. However, most trees can be trained into an espalier of some kind. Fruits such as peaches and nectarines, that fruit on new wood require different pruning maintenance so that fruit production isn't impacted.
The science behind espaliering trees
Espaliering encourages increased flowering and fruiting in large part due to hormones and sap flow. The main hormones involved are Auxin, Cytokinin, and Ethylene. Understanding these plant hormones will help to control tree's response when training espaliers, and fruit trees generally.
Auxins are produced in growing shoot tips and move down the stem. The highest concentrations are closest to the tip. The purpose of Auxin is to suppress the opening of buds below the growing tip. You have probably heard this referred to as apical dominance. In nature this is important to a young seedling as by promoting the growth of the shoot tip at the expense of the growing points located lower down the stem, the plant is better able to compete for sunlight with its neighbours. The strength of this apical dominance contributes significantly to a plant’s characteristic shape. Strong apical dominance yields a single-leader growth type and narrow conical shape—think of a pine tree. Weak apical dominance yields more diffuse branching, such as that seen in flowering dogwood.
However, when you prune and remove a growing tip, you remove the source of the bud-break-suppressing auxin, allowing the lower bud(s) to break and grow. This is where cytokinins come into play. They are produced in the roots and then move up the trunk with the sap and into the shoots, stimulating lateral plant growth. The currently accepted hypothesis is that auxins suppress the action of cytokinins. Remove the auxin, and the cytokinin can do its thing. Gardeners can also use a technique called notching, where they cut through the bark, xylem, and phloem tissues above a bud that they wish to grow into a new branch. This cuts off the downwards flow of auxin and encourages the bud to grow into a new branch.
Ethylene is the third hormone that can help a budding gardener. It is produced by the tree in response to wounding or branch bending, and one of its effects is fruit bud formation, which helps explain why branch bending and the regular pruning of espaliers promotes fruiting.
Controlling sap flow is the second part of the equation. This is linked to a tree's vigour, both of the rootstock's and variety grafted on it. A rootstock can only pump nutrients so far. In standard trees, this controls the overall height of the tree. In espaliers, as branches are moved from vertical to a horizontal position, you make it more difficult for sap to flow and therefore slow down the sap flow to the tip of the plant. This enables the plant to push out more lateral growth. As the growth rate of that branch slows down, it puts more effort into growing fruit buds.
So espaliers work because, through pruning and training, you control the hormones and sap flow to limit vegetative growth and instead encourage the tree to direct its energy into fruit production. If you look at the styles of espaliers below you will see they accomplish this in one of two ways. Firstly moving branches to a more horizontal position, such as in the horizontal cordon, fan, and palmette oblique styles. The second way is by creating multiple apical leaders. The auxin suppresses excessive lateral growth, but multiple leaders control the vigour of the tree, encouraging more flower and fruit production. Examples are the vertical cordon and U cordons. Some styles such as the palmette verrier make use of both of these techniques.
Styles of espaliers
What you can do is really only limited to your imagination. But be aware if espaliering fruit trees that certain styles that are more decorative may not be as productive as others.
The most traditional style with branches growing horizontally out of one central trunk. A single tier is often called a “rope” or a "step-over", although technically a step-over is where the trunk is bent at 90 degrees, rather than two branches forming a single tier. It is more common that there are multiple tiers, generally three tiers of branches but could have as many tiers as your rootstock can handle. Cordon espaliering can be used to form living fences or to increase yield in small orchards.
The other common espalier style is the Fan. This is perfect for trees such as apricots, plums, peaches, and nectarines, that fruit on new wood, require the continued renewal of branches to ensure fruit production. These trees also tend to have brittle wood and branches that are prone to snapping if you attempt to train fully horizontal, or bend at sharp angles needed for other espalier designs. You will sometimes see this called “informal”. However the purpose of the fan style is used to create branches that can be renewed as the tree ages for trees that only fruit on new wood. The informal style is more naturally shaped, generally just tying branches where they are, onto a single plane.
Note that these styles have been described for your reference. The Potted Pear does not create all of these styles.
Step-over
Also known as a “rope”, these are usually only 30-50cm high. Step-overs are often used as borders for vegetable gardens that can be stepped over into the garden. Using smaller trees can increase the yield in small sections by having many smaller trees of different varieties, fruiting over a long season.
This very versatile style can be modified to fit almost any space. We suggest starting with one of our maiden trees if you wish to grow this style.
Cordon
A single vertical cordons on a dwarfing rootstock such as M9 or M27. If you have limited space but want a large variety of fruit, single cordons can be planted 60-90cm apart and do well in pots. Cordon espaliering can be used to form living fences or to increase yield in small orchards by having many smaller trees of different varieties, fruiting over a long season.
This very versatile style can be modified to fit almost any space. We suggest starting with one of our maiden trees if you wish to grow this style.
Oblique Cordon
A single vertical cordons on a dwarfing rootstock, such as M9 or M27 planted on a 45 degree angle. Cordon espaliering can be used to form living fences or to increase yield in small orchards by having many smaller trees of different varieties, fruiting over a long season.
This very versatile style can be modified to fit almost any space. We suggest starting with one of our maiden trees if you wish to grow this style.
Horizontal Cordon
The most traditional style with branches growing horizontally out of one central trunk. A single tier is often called a “rope” or a "step-over", although technically a step-over is where the trunk is bent at 90 degrees, rather than two branches forming a single tier. It is more common that there are multiple tiers, generally three tiers of branches but could have as many tiers as your rootstock can handle. Cordon espaliering can be used to form living fences or to increase yield in small orchards.
This very versatile style can be modified to fit almost any space.
Vertical Cordon
Vertical cordons can just be one trunk on a dwarfing rootstock (just called a cordon), but more often several vertical branches arise at regular intervals from a low horizontal branch coming off the central trunk, forming a candelabra shape. By creating multiple "trunks" as it were, you control the vigour of the tree and direct more energy into flower and fruit production. Single cordons can be planted on a 45 degree angle to create an Oblique Cordon.
This style creates a dramatic focal point in any garden.
Double U Cordon
This is a good shape because you are breaking the vertical cordons twice, halving the sap with each divide and slowing the whole tree down, This means that there is less chance of one limb taking over, or the whole tree being too vigorous. It is possible to create triple or even quadruple U- cordons.
The Potted Pear does not offer this form at this stage but we hope to do so in the future.
Palmette Verrier
Branches are shaped into a U as the horizontal branches are turned up at the ends. This creates a nice definition between trees planted against a wall. A beautiful style that is also productive.
The Potted Pear does not offer this form at this stage but we hope to do so in the future.
Palmette Oblique
If you are wanting to espalier trees that fruit on new wood, but want something more formal than the Fan style, the Palmette Oblique is for you. They are formed by retaining the central trunk and training the branches at a similar angle to oblique cordons. You can angle the branches to fit the space you have available. However, the branches are never taken to horizontal like the traditional espalier. This method of espalier is well suited to fig, peach, gooseberry, and nectarine.
The Potted Pear does not offer this form at this stage.
Fan
This espalier system is perfect for trees such as apricots, plums, peaches, and nectarines, that fruit on new wood, require the continued renewal of branches to ensure fruit production. These trees also tend to have brittle wood and branches that are prone to snapping if you attempt to train fully horizontal, or bend at sharp angles needed for other espalier designs.
The Potted Pear does not offer this form at this stage.
Informal
This espalier system is possibly the easiest and most versatile to learn. This is often lumped together with the fan. However the purpose of the fan style is used to create branches that can be renewed as the tree ages for trees that only fruit on new wood. The informal style is more naturally shaped, but still in a single plane. This requires only simple pruning. This is a good style for citrus trees.
The Potted Pear does not offer this form at this stage.
Arcure
Another advanced espalier form, suited to creating long screening. In this form the maiden trees are planted at a slight angle to the right about 1m apart. Curve the trunk into a semi-circle and tie to the support. Pinch off all shoots except the center shoot at the top of the curve. Allow the remaining shoot to grow over the summer, then bend it back in the opposite direction and tie. Keep repeating this procedure until the fence has reached its required height. Branches bent downward cease terminal growth and encourage abundant fruiting.
Because this style isn't symmetrical, it is not suited to being grown in pots long term. The Potted Pear does not offer this form at this stage.
Serpentine
A relatively easy form, the serpentine has a strong central leader that has been trained into an 'S' shape with little or no side branching. Perfect for formal gardens and courtyards. If you wish to try your hand at this very decorative style, firstly ensure you have a stable support structure in place. If you have a stake in a serpentine shape this helps accentuate the form. Then plant a 1 year old maiden tree and train in an 'S' pattern, removing any side shoots.
This style can be grown in pots and a dwarfing or semi-dwarfing rootstock is recommended. Looks particularly striking when several serpentines are in a row.
The Potted Pear does not offer this form at this stage.
Belgian Fence
A relatively simple form used to create long screening. Three or more V-shaped espaliers are woven together to create a lattice effect. The trees on either end are modified to finish to maintain the intended finished edge. This is a beautiful way to create a row of differing varieties of fruit trees.
This style can be grown in pots, however as the trees age they usually form natural grafts where the branches cross. This makes moving, and repotting difficult so it is not recommended that they are kept in pots if woven together as a fence. The Potted Pear does not offer this form at this stage.
Drapeau Marchand
An advanced espalier form, suited to creating long screening. If you wish to try your hand at this very decorative style, firstly ensure you have a stable support structure in place. Then plant 1 year old maiden trees on a 45 degree angle, about 1.5 - 2m apart. Then allow branches to grow on the top side, spaced about 30cm apart until they touch the trunk of the tree next to them.
Because this style isn't symmetrical, it is not suited to being grown in pots long term. The Potted Pear does not offer this form at this stage.
Losange
An advanced espalier form, suited to creating long screening. Similar to the Belgian Fence, but with additional branches allowed to grow at 90 degrees off the first two branches, back toward the centre. If you wish to try your hand at this very decorative style, firstly ensure you have a stable support structure in place. Can be a stand alone tree or two or more trees can be woven together to create a lattice effect.
This style can be grown in pots, however as the trees age they usually form natural grafts where the branches cross. This makes moving, and repotting difficult so it is not recommended that they are kept in pots if woven together as a fence. The Potted Pear does not offer this form at this stage.
Heart
Branches are shaped into a V to begin with then are turned inwards and down to form a heart shape. While relatively simple to create it requires more care to maintain the shape, particularly if the variety or rootstock is vigorous.
The Pottted Pear does not offer this form at this stage.
Circle
Similar to the Palmette Verrier, but the branches are curved until they are touch at the top, forming a circle. A beautiful style that is useful for trees with wood that is too brittle to bend at sharp angles.
The Potted Pear does not offer this form at this stage.
How to do it?
Espalier is a horticultural technique that involves training a tree to grow in a two-dimensional, flat form against a wall, fence, or trellis. This not only saves space but also creates a decorative and functional garden feature. Here are step-by-step instructions on how to espalier a tree:
Step 1: Choose the Right Tree and Location:
Select a young tree with flexible branches. Semi-dwarf - standard varieties are ideal for espalier. While dwarfing rootstock is good for single cordons, I personally don’t think that dwarfing rootstock had the vigour to supply sap to large espalier forms
Choose a sunny location with well-draining soil near a wall, fence, or trellis where you want to train your tree.
Step 2: Install the Support Structure:
Install a sturdy support structure such as a trellis or wire system against the wall or fence. Ensure it's firmly anchored to the ground or wall. You can also use a frame made of bamboo or similar material to hold the branches in place. It is recommended for horizontal cordons that each row be between 30 - 50 cm apart.
Step 3: The First Cut:
In late winter or early spring, when the tree is dormant, is the best time to prune deciduous trees. Select the main stem or trunk, which will be the central leader, and trim it to the desired height, which is usually the height of the first row of your support structure.
This takes a bit of courage to so drastically prune a newly bought tree. But this will prompt the tree to produce new branches from bud nodes at approximately the height of the cut.
For a horizontal cordon form you will want to keep three branches near the first cut. Two of these will form the first horizontal cordon, the third will be allowed to grow up to the desired height of the next cordon.
Depending on the tree you have, you may be able to identify branches you are able to keep for your espalier design. These will need to be young and flexible branches to ensure that branches don’t snap when bending them the support frame.
Step 4: Attach the Branches to the Support:
Once the new growth begins to take off gently attach the selected branches to the support structure, spacing them evenly and horizontally. To keep encouraging the branches to grow longer make sure that the last 20 or 30 cm the branch tip is pointing up. If you tie the entire length of the branch to the horizontal support the branch will most likely stop growing.
Be careful not to damage the branches while securing them to the support.
Step 5: Train the Branches:
As the tree grows, guide the branches along the support structure. Use soft twine or garden ties to secure them in place.
Aim to create the desired pattern or design, such as a fan, candelabra, or horizontal cordon. Regularly adjust and train the branches to maintain the shape.
Step 6: Prune and Maintain:
Prune your espalier tree during the dormant season (usually in late winter or early spring) to remove any unwanted growth, maintain the shape, and encourage fruit production.
Pruning will involve cutting back new shoots and maintaining the desired design.
Step 7: Fertilise and Water:
Fertilise your espalier tree according to the specific needs of your chosen tree variety. Generally, a balanced fertiliser in spring is a good start.
Keep the tree well-watered, especially during dry periods, to ensure healthy growth and fruit development.
Step 8: Mulch and Monitor:
Apply a layer of mulch around the base of the tree to retain moisture, suppress weeds, and regulate soil temperature.
Regularly monitor the tree for pests and diseases, and take appropriate action if any issues arise.
Give it a go
Espaliering a tree is a rewarding and creative way to grow fruit trees while enhancing the aesthetics of your garden. Patience and regular maintenance are key to achieving a successful espaliered tree.