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noun: espalier; plural noun: espaliers
a fruit tree or ornamental shrub whose branches are trained to grow flat against a wall, supported on a lattice or a framework of stakes.
I've seen some beautiful forms of espalier trees. This is my attempt at espaliering my Violet De Bordeaux. It's still a young tree so the limbs are very pliable.
I'm not quite sure honestly of the final shape but it'll be fun to start training the plant now at such a young age.