How to Train and Prune Apple Trees? Latest Techniques and Methods Tutorial

The apple tree is a deciduous tree of the genus Malus in the rose family (Rosaceae). Trees can usually reach 15 m in height, but cultivated trees generally grow only about 3-5 m tall. It originated in central and southeastern Europe, Central and Western Asia, and Xinjiang, China. In 2013, world apple production was 80.82 million tons, unquestionably making it the king of temperate fruits. Now let us take a look at apple tree training and pruning techniques!

Principles of Apple Tree Training and Pruning

Apple tree training and pruning should be based on differences in orchard site conditions, cultivar, rootstock, density and tree age, selecting a reasonable tree shape according to the site, the orchard and the tree, and adopting corresponding pruning methods to regulate the relationship between growth and fruiting, so as to achieve the goals of a vigorous and balanced tree, early bearing, high yield, high quality and high efficiency.

Indicators for Apple Tree Training and Pruning

1. Tree height: for dwarfing trees, trunk height 0.8-1.0 m, tree height 3.0-3.5 m; for standard (vigorous) trees, trunk height 1.0-1.5 m, tree height 2.5-3.0 m; trees should not touch each other within the row, a 1-1.5 m working aisle should be kept between rows, and canopy coverage should be 75%.

2. Branch number: after pruning, about 80,000 branches per mu should be retained on apple trees, of which medium and short branches account for 70%, and terminal flower buds account for about 30%.

3. Branch groups: in the early stage of the open-center form, the main focus is on developing small and medium-sized branch groups, with emphasis on selecting various branch groups on the main branches that grow obliquely or downward; in subsequent years these are gradually developed into large, three-dimensional, pendulous fruiting branch groups. In the spindle form, small main branches are borne as branch groups with an open angle.

Spindle Pruning of Apple Trees

1. Apple tree structure: tree height 3.0-3.5 m, trunk height 0.7-0.8 m, with 20-25 small main branches arranged on the central leader at a spacing of 10-15 cm, main branch angle 90-100°, shorter at the top and bottom and slightly longer in the middle, the rate of contact between trees within the row not exceeding 10%; mainly applied to dwarfing and spur-type cultivars and to standard temporary trees.

2. Pruning of young trees: the key points for pruning young trees (1-5 years) are to form a good tree shape and promote tree vigor, laying the foundation for early fruiting and high yield. Do not head strong seedlings; for weak seedlings (below 1 m), head at a plump bud. Remove vigorous branches on the central leader to strengthen the dominance of the central leader. According to the requirements of the tree shape, starting from 70 cm above the ground, select and retain small main branches at 10-15 cm intervals, following the principle of spiral arrangement, and select them upward year by year to meet the requirements of the spindle shape. Remove branches growing on the upper side of the branch, excessively dense branches and overlapping branches.

3. Pruning of mature trees: the key points for pruning mature trees (≥6 years) are to perfect the tree structure and develop fruiting branches. The central leader extends vertically and the small main branches extend on a single axis, with a branch-to-trunk ratio of 1:3 being appropriate. Small main branches are managed dynamically; by the method of removing large ones and keeping small ones, and removing old ones and keeping new ones, excessively large main branches exceeding 1/3 of the trunk are deliberately and mainly removed, and small main branches are developed in a spiral arrangement. To develop fruiting branches: first, select and retain moderate lateral and pendulous branches as fruiting branches; second, remove vigorous branches on the upper side of small main branches.

4. Pruning during the growing season: before and after bud break, make notches above the buds at positions on the central leader and main branches where branches are lacking, to stimulate new shoots. Bend branches according to the requirements of the target tree shape; 1-2 year old branches should be bent from mid-August to mid-September, and branches 3 years and older should be bent from after spring flowering to mid-May (before bagging), using the steps of “one push, two rub, three press, four fix” so that they are bent to the required angle and kept straight without “bowing.” For main branches that grow extremely vigorously and are not easy to flower, make ring cuts from late May to early June; remove useless branches such as suckers, water sprouts and excessively dense branches; when the central leader and the extension shoots of the main branches of young trees reach 40 cm, pinch the tips to stimulate branching.

Open-Center Pruning of Apple Trees

1. Apple tree structure: tree height 2.5-3.0 m, trunk height 1.0-1.5 m, retaining 4-6 relatively large permanent main branches, with a base angle of 75°, a middle angle of 85° and a tip angle of 80°, arranged to fill the spaces, with the main branches extending indefinitely; large, medium and small fruiting branch groups are evenly distributed on the main branches, and the branch groups are pendulous; mainly applied to standard and semi-dwarf fruit trees.

2. Pruning of young trees: the key points for pruning young trees (1-7 years) are to form a good tree shape, promote tree vigor and expand the canopy, laying the foundation for early fruiting and high yield.

① After planting, head at a plump bud; shorten the central leader and the extension shoots of the main branches at plump buds to stimulate vigorous shoots. Leave the remaining branches unpruned, and remove branches below 1.0 m on the trunk.

② According to the requirements of the tree shape, starting from 1.0 m above the ground, following the principle of spiral arrangement, select and retain branches with a relatively large base angle and vigorous growth as permanent main branches at intervals of about 40 cm, and support and boost their vigor to accelerate extension growth, so as to meet the requirements of the open-center framework.

③ Remove competing branches, branches growing on the upper side of the branch, excessively dense branches, overlapping branches and diseased and pest-damaged branches; train lateral and pendulous branches on the main branches into pendulous branch groups to promote early fruiting.

④ On the premise of not affecting the growth of the scaffold branches, temporary branches not selected as main branches should be retained as much as possible, to promote the branches to transform as quickly as possible, form flower buds and bear fruit as early as possible.

3. Pruning of mature trees: the key points for pruning mature trees (≥8 years) are to develop fruiting branch groups, expand the canopy, complete training and achieve three-dimensional fruiting.

① For trees with vigorous growth and a relatively large canopy, gradually complete the heading back to open the center within 3 years. In the first step, select two relatively weak branches to replace the leader and head back to half of the intended height; in the second step, remove one main branch at the heading point, keep one main branch, and remove vigorous and upright branches on the main branch; in the third step, head back again to the required height (that is, the height of the uppermost main branch from the ground), completing the open center.

② For trees of moderate to slightly weak vigor, the heading back can be done in place in one operation, leaving a 20-30 cm protective stub, which is removed after 1-2 years.

③ Remove temporary branches year by year to make way for the expansion of permanent branches. First, remove temporary branches that grow on the trunk, affect light and are excessively large. Second, according to the light conditions of the tree, appropriately remove main branches that are too low.

④ Developing branch groups: use pendulous branches and secondary shoots from fruit spurs to extend continuously to develop medium-sized pendulous fruiting branches; use vigorous lateral branches on the main branches, bend them by pulling to change their direction, moderate them to form fruiting branches, and after fruiting use the secondary shoots from fruit spurs to extend continuously to develop large and medium-sized pendulous fruiting branch groups.

⑤ Renewing branch groups: for branch groups that have borne fruit for many consecutive years and whose growth vigor is obviously weakened, timely renewal and rejuvenation can be carried out by the methods of thinning, cutting back and removal.

⑥ Notes: promptly protect the relatively large wounds caused by branch removal; for orchards with a dense canopy and poor light, planned thinning of trees should be carried out. For branch groups that have borne fruit for many years and whose growth vigor is obviously weakened, timely renewal and rejuvenation can be carried out by the methods of thinning, cutting back and removal.