Left to grow in a natural pattern, the crown of an apple tree develops a rounded shape. The lower branches receive only 30 percent of full sunlight and bear poor quality fruit. Topmost branches bear the best fruit but out of easy reach. Correct training and pruning produces a smaller tree with a pyramidal shape, which allows convenient harvesting. Uniform light distribution throughout the canopy creates evenly ripening, high-quality apples at all levels of the tree.
Training Apple Trees
Cut back first-year apple whips to 30 inches tall. Pruning the transplanted trees too short causes sucker production rather than strong branches. Early in the summer, select the strongest topmost vertical shoot to serve as the central leader. Prune out any competing shoots by cutting them back to the branch collar. In midsummer, remove all branches growing less than 18 inches from the ground.
Select fruit-bearing scaffold limbs located several inches apart vertically and oriented at 90-degree intervals around the trunk. Eliminate whorls--groups of branches sprouting at the same level--by trimming out all but one of the branches in the knot. Use limb spreaders between branch and trunk to shift vertical growth to a more horizontal pattern. Horizontal branches develop wide, strong saddles connecting to the trunk of the tree. Vertical forks often break when loaded with fruit. Properly spreading the limbs could take two years to develop. Place branch spreaders early in the limb's second year.
Prune to select a new leader early each summer as the tree matures. If done before the new wood hardens, competing shoots easily pinch off. Support leaning trees by tying the leaders to wooden stakes. Use garden twine and keep the lashings loose. In midsummer, head back unwanted vertical branches by tip pruning and remove any sucker shoots.
Cut out all but scaffold branches during the winter dormancy. Select new levels of scaffold branches from the previous summer's new growth. At lower levels, remove any crossed branches or branches growing directly beneath the main scaffold limbs. Cut out vertical growth that shades fruit-bearing scaffold limbs. Remove any branch with a weak saddle or correct its growth with a limb spreader if the branch grows in a good location.
Head back upper scaffold branches if they outgrow lower limbs. Cut back to just short of a healthy side branch. Correct drooping limbs by thinning out side branches and cutting back the branch's leader. On varieties with heavy fruiting spur growth, cut out any weak or dead twigs and remove alternating spurs to reduce fruit set and improve the crop.