The term espalier refers to the practice of training a tree to grow along a flat vertical surface such as a stone wall or the side of a house. Espalier can be performed on almost any tree as long as the training begins when the tree is young. Although apple trees can also be trained using espalier, it should be noted that the tree will not produce as many apples due to the reduced number of tree limbs.
Purchase a a dwarf or semi-dwarf variety of an apple tree seedling. Seedlings are young trees that are 1 to 3 feet tall.
Find the best area to plant the small apple tree seedling. The ideal location is a south or west facing location that receives plenty of sun and has good drainage. The location must also be near a flat vertical surface such as a house, shed, wall or fence.
Use a tape measure to measure a height of 48 inches above the ground and mark it with a pencil. Draw a line from the mark to the ground. This measurement will be the height of the tree and the guide for the tree trunk.
Measure a height of 16 inches above the ground on either side of the vertical line. Mark these points with a pencil. Draw a horizontal line from the marks to the line for the trunk of the tree. This set of lines will guide the lowest set of branches.
Measure two additional sets of horizontal lines at 32 inches and 48 inches above the ground and mark them with the pencil. Draw a horizontal line from the marks to the line for the trunk of the tree. These measurements create two additional branch sets for a total of three branches on each side of the trunk.
Insert the heavy wire into the ground along the vertical line. Attach it to the vertical surface using staples or wall mounts.
Use pliers to twist pieces of wire around the main vertical wire to represent each branch. Attach these wires firmly to the horizontal lines using staples or wall mounts.
Plant the apple tree seedling by digging a large hole that is about 3 feet deep. The hole should be four feet away from the vertical surface. Insert the apple tree seedling and fill in the hole with equal parts of compost and soil.
Use pruning sheers to cut the main trunk of the tree at a 45 degree angle at the point where the tree meets the first set of branch wires. Allow the tree to grow until it produces shoots that are 5 inches long.
Tie a branch on the right side of the lowest wire branch using garden tape. Repeat on the left side to create the lower branches of the tree. Trim off all other limbs using the pruning shears.
Allow the tree to grow until the first horizontal limbs reach 75 percent of the length of their guide wire. This may take several months and in the mean time, the main trunk shoot should be regularly pruned to a height of approximately 6 inches until the horizontal branches reach the correct length.
Stop pruning the main trunk shoot and allow it to grow until it reaches the second level of guide wires. Select two branches from either side of the main trunk and use garden tape to tie them to the second level of guide wires. Allow the tree to grow until the second horizontal limbs reach 75 percent of the length of their wire.
Repeat the process to form the third level of branches, and after that, keep additional vertical shoots pruned to prevent further vertical growth.