Trellising is a gardening technique used to improve a tree's growth and production, enhance its attractiveness, increase usable space and -- for fruiting varieties -- to prevent rotting. Specifically, espalier is the method used to grow and shape woody perennials through careful pruning techniques. Espaliered plants can be used to create a focal point in a garden or to add color to a large, blank wall. Though the pruning and training required for espalier is a continuous project, it yields benefits for both tree and gardener.
Plant a 1-year-old tree 8 inches away from the trellis, leaving an additional 4 feet of open trellis on either side. This extra space will give the tree room to grow. It's best to plant in late winter or early spring when the tree is still dormant.
Tie young shoots loosely to the trellis as they begin to develop in spring and early summer, using a soft string or twist tie. Young shoots include all new plant growth, such as stems, flowering stems, flower buds and leaves.
Cut away any new shoots that project away from the trellis and cannot be tied flat. It is best to prune off unwanted shoots while they are young, since young branches are pliable and easy to remove. If your tree is fruit-bearing, remove all fruit in addition to unwanted shoots to encourage tree growth.
Prune outward-growing shoots and fruit again in the second growing season, just like you did in the first. In the third season, allow fruit to grow.
Check the ties twice a year and loosen as needed. As the tree grows, the ties may become too tight and cause a ring of missing bark -- called girdling -- to form.