I'm starting with the two dwarf apple trees, since they seem to have the most potential. Both get plenty of sun and have a small form factor that will allow them to be cared for properly. In the last few years, they have been neglected and run wild, a bit. So I basically need to start with first principles and set them back on the right track.
These two trees flowered in the first two weeks of April. One has set fruit, and the other is still in flower.
Step One. The first thing I needed to do was correct some obvious problems with the overall growth of the tree. Both of the trees had a wild hare branch that went shooting straight into the air like a water spout. These obviously had to be removed.
- Remove all water spouts.
- Remove all suckers growing from the base or from the trunk below 18".
- Remove all dead wood and broken branches.
- Remove weak branches hanging from the bottom of the limbs.
- Remove branches that are growing back toward the center or trunk.
Finally set the overall height of the tree. The maximum height is six feet, though some trees would do better if they were even shorter. Use your 6' rod to accurately measure the height at which to cut your leader.
Once complete, the tree immediately looked better.
Step Two. In renovating the tree, identify the primary scaffold branches. There should be 3 branches at each whorl or tier. The lowest tier can have 3 or 4 branches as scaffolds. These should be strong and extend at a 60 to 80 degree angle from the trunk. All other branches that attach directly to the trunk should be removed. It can help to mark these scaffold branches in some way to make it easier to go on. Use flagging tape, hanging labels or even diluted latex paint. Primary scaffolds are color coded to green.
These apple trees use a central leader profile. (In this case, the central leader is clipped at 6 feet to limit the height of the tree so it is technically a modified central leader.) The central leader profile usually has two tiers of scaffold branches.
Tiers should be at least 18" apart. So once you've identified your 1st tier scaffold branches, travel 18" to 24" up the trunk and identify a second tier or whorl of lateral branches. The second tier should have only 3 scaffolds. Once again, identify the three scaffold branches of the second tier and mark them in some way.
Using a thinning cut at the branch collar, remove any other branches from the trunk except the primary scaffolds you have identified.
The primary scaffold of the lower tier should extend 2 to 3 feet from the trunk, depending on the overall size of the tree. One of my apple trees is a smaller one and more graceful, and a 2-foot scaffold is appropriate. The tree pictured above is more vigorous and can support a 3-foot scaffold. The scaffolds of the upper tier should be shorter than those below, usually 2 feet or less.
The drawing below shows a typical unpruned tree that is about 12 ft tall. (The lines represent 3-ft intervals) For a commercial tree, 12 feet might be a good height, but for a backyard orchard, we need to trim the height of this tree at 6 feet, near the second line. All the growth above that point is counter-productive.
Each of the yellow highlighted boxes shows the general location of the lower and upper tiers or whorls of branches.
As we look more closely at the lower right scaffold branch in the drawing, several things become clear. The orange branches are too close to the trunk to be saved, and too long to be fruiting wood. They also hang below the horizontal, making the overall branch weaker. These orange branches will likely have to be pruned away with thinning cuts.The yellow branch is not part of this scaffold branch; it belongs to a neighboring scaffold. Since it branches too close to the trunk and then immediately comes over and crosses the green scaffold, it likely just needs to be removed as well.
The extent of the green line shows a 24" length, so our scaffold can end anywhere just beyond that point. That means that the magenta branch heading straight up is just not far enough along the scaffold to qualify as a secondary. And, it's growing the wrong way and is crowding other branches. Magenta needs a thinning cut to remove it. The two blue branches at the transition are good candidates for secondaries. If this is a young tree, I would separate them with wooden spreaders. Or, you could make a hard cut at the transition and prompt two new branches to grow.
Step Three. At the end of the primary scaffold, the limb should branch into two secondary branches. If they are not already present, use a heading cut just beyond two suitable buds to stimulate this growth. If they are present, head the primary branch just beyond them.
As before, identify the two secondaries for each primary scaffold and mark them in some way. Secondary branches are color coded to blue.
These two secondaries should extend from the primary another 24 -36". Secondaries should be headed at that length. Use your rods to accurately measure where this break should occur. I the drawing above, one of the blue secondaries is rather long and probably needs to be headed back by several inches. This cut may promote fruiting spurs to develop along it, but watch out for water spouts.
Secondary branches should not extend in height above the central leader, especially where it was cut at 6-feet. You may need to trim the central leader annually; make sure your trim the secondaries as well to remain below this tip.
Step Four.
Growing laterally from the secondary scaffolds are other, shorter branches. These are the source of your fruiting wood and may contain thickened spurs where your fruit will form. Since you are completing your pruning in summer, you can easily see where fruit and flowers have formed on these fruiting branches.
Identify the fruiting branches and separate them from non-fruiting growth spouts. Remove any that crowd other fruiting wood, or cross with them. These fruiting branches should be 10-12" long but that may differ with the variety of your tree.
Thin the fruiting branches to have at least 6" between them, and head them so that they don't grow very long past their 10-12". This fruiting wood should be unbranched, and not break up into smaller and weaker twigs. It may form 1/2" fruiting spurs off of itself to hold the flowers and fruit.
Color this fruiting wood, that is actually bearing fruit, with a red paint wash. Next year, we will trim off all new growth back to this growth ring, where the paint wash stopped. Next year, as it bears fruit, we will give it a purple wash, and the following year, we will give it a blue wash.
When fruiting wood has a blue wash, it means it has been in production for several years and we should then check it to make sure it is still strongly setting fruit. If it is, we let it go another year, but if it drops off in productivity, we should cut it back and promote new fruiting wood to develop.
Step Five.
At this stage all the branches on the tree should be identified. Anything that isn't immediately identifiable at this point should be pruned away. The tree should be more compact, and yet the central area should be more open, allowing light and air to reach the center of the tree.
For this step, clear away all branches that were pruned from the tree. Do not allow them to lie on the ground under the tree. Rake away any fallen leaves or remnants of fruit from last year. You want to keep the site clean to prevent fungus and insects from finding a refuge to overwinter and renew their attacks.
With a mower, cut the grass beneath the tree very short. Apply 4" of mulch under the drip line of the tree, leaving a bare ring around the trunk with no mulch.
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