Espalier – Two-Dimensional Pruning for Trees and Shrubs
Marianne C. Ophardt
Washington State University Extension
Area Horticulture Specialist
Trees and shrubs are part of our three dimensional world. It takes an adventuresome gardener to turn a three dimensional plant into one with only two dimensions. Espalier is the art of pruning that involves controlling tree and shrub growth in a single plane... with the support of a building wall, fence, or trellis. This type of pruning is an ancient art that dates back to Roman times and was later refined by medieval Europeans to save space in the walled gardens around castles, cathedrals, and monasteries. They were able to reduce the space needed to grow fruit by keeping the growth relatively flat against garden walls... leaving open space for other garden crops.
Espaliering also proved useful in cooler climates with shorter growing seasons. By espaliering fruit trees against south and west facing walls, early gardeners found that they could take advantage of the extra heat in these situations, producing fruit in areas where their climate was usually a little too short or too cool to produce fruit. These south and west facing sites warmed up earlier in the spring and stayed warmer later in the season.
Another advantage to using espalier techniques with fruit trees was the effect espaliering had on the trees. Espaliered fruit trees usually come into bearing at an earlier age and are generally more productive with deeper fruit color. This is because of branch angles and the increased light penetration to leaf surfaces that result from the single plane.
The technique of espalier pruning is practiced by some commercial orchardists today because of the early bearing and productiveness of espaliered trees. Home gardeners and landscapers often practice espalier pruning for its decorative potential. Using espalier techniques, gardeners can create screens that don’t take up much room and have a softer look than fences or brick walls. Espaliered plants can also provide decoration for large, monotonous windowless building walls.
Gardeners should take note that espaliering is a technique that takes time and some expense. You must select the right type of plants and the right site along with making sure you have adequate support for the plant. Espaliering a tree or shrub involves pruning and training over time to develop and maintain the framework.
Let’s first chat about what types of plants lend themselves well to the art of espalier. Typically you want plants that have long, flexible branches. Plants with short or stiff branches are hard to train. You should also consider the mature height of the tree or shrub. A tree or shrub, whose mature height is much greater than the wall, fence, or structure you plan to train it too, will be unsuitable. Favored shrubs for espalier include cotoneaster, forsythia, holly, Pfitzer juniper, Kousa dogwood, pyracantha, winged euonymus, flowering quince, star magnolia, and viburnum. Favored trees for espalier include apple, crabapple, and pear. Fruit trees that bear their fruit on long-lived spurs are the easiest to espalier. Fruit varieties that have predominantly spur-type growth, such as Red Delicious, Golden Delicious, and Braeburn apple cultivars along with Bartlett pears, work the best.
In selecting a plant, pick a young, vigorous tree or shrub that has a few well-balanced limbs off the main trunk. Wait until after the plant becomes well established before you perform the extensive pruning needed to start your espalier framework. In some nurseries you might be able to find plants that already have some initial espalier training. This will make getting started easier.
When planting your tree, be sure to plant it properly to help insure a tree with a healthy root system. If you’re planting your tree or shrub against a solid wall, the plant should be situated about six to ten inches away from the wall to allow for air circulation behind the plant.
You will need to provide a sturdy support on which to develop your plant’s framework. This can be done by stringing heavy wire of at least 12 to15 gauge from eye bolts on the fence or wall. You can also develop your espalier on a free standing trellis. Just be sure that the trellis is sturdy enough to support the weight of both branches and potential fruit. When making a trellis for fruit trees, use 4x4 pressure treated posts, sinking the posts two feet into the soil. Set the posts about ten feet apart, securing the end posts with stakes and guy wires. With fruit trees you’ll probably want two to three levels of wire with the bottom wire situated about 18 inches from the ground.
Designing your espalier is the fun part. A well designed and trained espalier is a real work of art. If you’re doing your first espalier, you should probably start with a simple design. Some of the most common designs are fan-shaped, T-shaped, palmate, pinnate, chevron or V-shaped. More difficult designs are cordon, basket weave, and candelabra. Check pruning books in your local library for diagrams of these designs. With many of these designs, you’ll need to pattern your wire supports accordingly. If you want something less formal, an asymmetrical informal espalier can be created by allowing the plant to grow and dictate the design. Training in this case only consists of keeping growth in one plane.
After your tree or shrub is planted and you have its supports in place, you’ll begin its training. Spread the main branches onto the supports and tie them in place. You need to be careful not to crack or break branches when you bend them into the wanted position. New growth early in the summer will be more flexible than older branches.
When tying down the branches, use soft string, strips of rags, rubber grafting bands, plant ties, or raffia. Avoid using wire that can cut into the bark. Tie the branches to the supports loosely, leaving some extra room for the branch to grow. Check the ties every three or four months to be sure they aren’t restricting or damaging the branches. Replace the tie if its hampering growth.
Branches that aren’t part of the design should be pruned off the spring after planting. Shape the plant every month or so, removing branches or twigs that aren’t in the correct plane of growth. Training of simple designs may take only two or three years to develop, but more intricate designs will take longer to achieve.
Espalier is a fun way to relieve the monotony of a blank wall or fence. Anyone who has the heart and patience of a gardener as well as the soul of an artist should give it a try. If you’re successful, you’ll have an interesting and attractive landscape accent... if not, you’ll have a really strange and ugly landscape blemish.
Garden Note: In our region, gardeners should avoid espaliering on south and west facing walls. Our intense summer sun and heat will be more than most types of plants can endure, plus plants in these types of exposure are more prone to winter injury. Northern exposures may not provide adequate light for flowering and fruiting trees and shrubs. East facing walls are probably the best bet.