The trellis may be of several types, depending on how difficult an espalier project you want to attempt. A wooden fence, wood, iron or steel posts, cattle or deer fencing or chicken wire can also support espaliered fruit trees. There are several espalier designs, many with fancy names, including the single vertical cordon, the single horizontal cordon, oblique palmette with fixed limbs, Baldassari Palmette, the Belgian fence, lepage espalier with three branches, the U double, the verrier candelabra and the drapeau marchand. All fruit trees can be espaliered, but home gardeners usually prefer apple, pear and plum trees. The tree must be in its first year or two of growth in order to be espaliered.
Older trees are more difficult to train, as bending mature branches can take one to three years.
Any gardener attempting the espalier technique should be aware of the time investment required for success, advised Penhallegon. An espalier project may take from five to 10 years from start to finish. Espalier training systems depend on a trellis, which may be quite elaborate. Build the lower, inner parts of the trellis first. Train the tree to it while the limbs are still flexible.