Espalier (ess-PAL-yer) is the practice of controlling plant growth so that it grows relatively flat against a structure such as a wall, fence, or trellis. In the 17th Century, espalier originally referred to the frame or trellis on which the plant was trained. Today, espalier refers to both the plant and the horticultural technique of actually training the plant.
Espaliered plants can be used to create a focal point and as a form of art. In an area where space is limited or where a plant is needed to accent a large blank wall an espaliered plant can be an outstanding landscape feature. A mature espalier plant will catch the eye of almost any visitor to your home.
An espaliered plant can be a high maintenance addition to the landscape --- so limit the number of plants you plan to espalier. Patience, skill, and creativity are necessary for a successful project. Large, fast growing plants such as a pear tree will require a large wall and will need many hours of pruning and training. On the other hand, a sasanqua camellia grows much slower and can be managed in a small area. If you espalier a fruit tree (apple, pear), select a cultivar that produces a large number of spurs and is grafted onto a dwarf or semi-dwarf rootstock. Grafting will not affect the size of the leaves or fruit but will reduce the overall size of the plant. Fruit such as plums and cherries can be espaliered but they bear their fruit on shoots from the previous season’s growth. Renewal pruning is necessary to ensure a continuous crop. Many vines (Boston ivy, English ivy, wisteria, climbing roses) can be trained as an espalier plant.
Trees and shrubs to consider include:
Study the lines of your house and make notes of any blank walls or fences --- a simple background is ideal for showcasing an espalier plant. Select a site that provides the normal growing conditions for the specific plant –- especially consider the amount of sunlight and soil drainage. Normally the best location for an espaliered plant is on the south- or east-facing wall. A north- or east-facing wall will minimize winter injury. Plants grown on a north facing wall will receive very little direct sunlight and will produce a limited amount of foliage growth ---- even fewer flowers and fruit. Planting close to a wall (especially a brick wall) will subject the plant to a unique microclimate. The brick absorbs heat during the day and releases heat at night. A south- or west-facing wall will be warmer in the winter---winter injury may occur on plants that are marginally hardy to the area.
Many nurserymen sell container-grown plants that have been trained to grow on a trellis. The plant is often 3 to 4 feet tall and growing in a 3-gallon container. While this may seem to be the easiest way to start an espalier, the plant may not be growing in the pattern you would prefer to use in the designated site. Often the easiest way to get started is to select a small 1-gallon container plant. With fruit trees select a small single stem unbranched plant (refereed to as a whip) or one that has very small side branches.
Prepare the plant site as you would for any other plant. Incorporate lime and phosphorus fertilizer as indicated on a soil test report. Pine bark mulch or other suitable organic matter should be incorporated when preparing a bed but not used when preparing individual holes. The plant should be planted 6 to 10 inches away from the wall to allow adequate room for the roots to grow, air circulation, and pest control. Set the plant the same depth it was growing in the container, water, and apply a 2- to 3-inch layer of mulch. Prune sparingly until the plant becomes established. Extensive pruning immediately after transplanting will delay new root development.
There are numerous espalier techniques to employ from the very simple, free-flowing natural and informal designs to complicated formal patterns. The most common formal styles are candelabra, tiered, basket weave, fan, cordon, pinnate, palmate, or diamond motif. Draw your design on a sheet of graph paper. This will help you determine the size of the espalier and the amount of construction material needed. Many designs may be difficulty to create without a physical guide on the wall. You may wish to build a frame or trellis in the shape of the design to help you train the branches.
There are several hardware items that will be necessary. For masonry walls, u-bolts, eye
bolts and eye screws are helpful. They can be anchored by using expandable lead shields, or plastic plugs in the mortar joints. You will need a carbide drill to make holes in masonry walls. For wooden walls use a 2 1/2-inch floor flange with a 6-inch galvanized nipple threaded over the end of the nipple and fasten with a wire roof clip. On the opposite end, attach a 3-inch turnbuckle so the tautness of the wire can be adjusted. A heavy gauge wire (12 or 15) should be strung between the eyebolts. Wire with a dark green or black insulation will help the wire blend in and be less noticeable. An alternative method is to build a trellis about 6 inches from the house.
Pruning and training will be a continuous project. Traditionally, the major pruning is done in late winter to early spring before new growth begins. There are several important factors to consider before pruning. Pruning during the dormant season or early spring will stimulate new growth. Pruning in mid-summer (June, July) tends to have a dwarfing effect. Pruning should not be done in late summer -- with the exception of removing a few small shoots. New growth could occur that might not have time to mature before a killing frost.
The time and amount of pruning should also take into account the age of the plant and when flower buds are formed. Young branches tend to be more flexible during the summer. One can bend and train them to supports as the season progresses.
Branches chosen to be part of the design can be tied with a soft string or twist tie (may need to be removed as the stem grows in diameter). Check the attachments twice a year and loosen as necessary to prevent growth constrictions. Branches not needed for the design should be removed. If the flower buds are remove during the initial training period, more plant energy will be directed into plant growth to complete the design. Branches that are part of the pattern should not be tip pruned until they reach their desired length. Side shoots should be allowed to grow to about 12 inches before they are shortened. Leave a few leaves after pruning. Touch-up pruning (pinching) should be done as needed throughout the growing season. mature espalier plant will catch the eye of almost any visitor the your home.
© Erv Evans, Consumer