@Shibumi, I just wanted to let you know that I haven't forgotten about you.

You know the saying
"You have to make hay while the sun shines" ? Well figuratively speaking I've been making hay for the past 4 days of welcome sunshine and warm weather (spring suddenly arrived with a big bang) and have been busting my butt transplanting as many as possible of my plants into the ground outside before the rains come again (supposedly) for another 4 days starting tomorrow night. So I will be back with my pruning suggestions once the rain has me cooped up indoors again but in the meantime I'm posting 2 short videos at the link below and commentaries for you that I think will be helpful.
The gardener posting the videos is an accomplished young man in Utah and when you read and watch his easy instructions and demonstrations you will notice that he did something very essential that you have not done but it really, really, really needs to be done first for Belgian espalier - he completed installing the solid construction of the entire permanently attached bamboo lattice work from end to end before he started doing any pruning or training of the little apple trees. You will see how that proceeded in the videos. Completing the permanent lattice work needs to be your number one top priority now before you do anything else with your trees. Seriously. You can put the whole bamboo thing together laying it on the ground and then lift it up into place to attach to the wires and frame.
And you have a GREAT sturdy lumber frame to support everything and build onto. If you are planning on leaving your center-most tree with a central vertical leader with trained laterals at the sides I would suggest that you attach one or two more horizontal wires to the wooden frame near to the top cross beam.
To put up and attach the full size bamboo lattice construction in place on either side of the wires you are going to have to detach the existing bamboo pieces from the wires and remove them from the branches they're on so the trees' branches can all be gently moved back out of the way while you hang the completed lattice up from the cross beam with rope and then attach the lattice to the wires. Then you can re-attach the branches to the bamboo. You'll notice it's a lot easier to visualize and quickly attach the branches to the full lattice once it is solidly up in place.
* A little tip for you, I use cheap plastic hair clips from dollar stores to temporarily clip branches to lattice work and wires. It's easier to move and relocate them and shift them around when making adjustments to the placement of the branches. The hair clips come in a variety of sizes, you'll find them in the hair care & accessories section of dollar stores.
One other thing you will notice this gardener commenting about in the video is that with Belgian espalier it's quite all right for you to have your trees spaced 2 feet apart and it's a common practise by many espalier gardeners to do so, sometimes with even less spacing than two feet. His trees are planted 2.5 feet apart and he has 9 trees in a row.
Video showing how to build the support structure for espalier fruit trees, how to prune dormant apple trees to set them up for espalier training, and how to train them to a lattice shape, Belgian f…
foodscapingutah.org
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