The correct way to prune apple trees in winter

Winter pruning of apple trees is an important part of improving orchard management, ensuring tree morphology, and increasing fruit yield and quality. It is winter now and many fruit farmers have finished picking their apples in their orchards. Let’s learn the correct method of pruning apple trees in winter.

1. Follow the "Three No-Cut" Principle

1. Don’t use inferior tools *

Buying a cheap pruning saw to save money is not only laborious but also produces poor pruning results. High-quality shearing and sawing tools can improve work efficiency, make cuts smoother, reduce tearing, and promote wound healing.

2. Do not neglect wound protection

The cut and sawed ends of apple trees need to be coated with protective agent in time to prevent them from drying out and cracking, and to avoid mold, drying out and rotting in the future. Protective agent should be applied immediately after cutting, especially for wounds with a diameter of more than 1 cm. Artificial bark, wound healing agents, etc. can be used to protect the wound for up to a year. Generally, wounds of about 2 cm can heal within the same year.

3. Don’t neglect disinfection

Apple tree virus diseases spread rapidly, and pruning tools are an important way for the virus to spread. Virus-infected trees should be marked before pruning, and the last pruning should be done. The saw should be disinfected every 2-3 hours using disinfectants such as 2%-5% caustic soda, 3%-10% trisodium phosphate, 75% alcohol or potassium permanganate solution.

2. Pay attention to tree structure transformation

1. Increase the height of the trunk

For apple orchards with low trunk height, it is recommended to gradually thin out the main branches less than 50 cm in height within 1-2 years so that the trunk height reaches 80-100 cm to improve field operations and fruit coloring.

2. Control the number of main branches

The number of main branches of the Red Fuji small-crown sparse-layered tree should be 6-7 in the early fruiting stage, and 3-5 in the peak fruiting stage. Maintain appropriate angles to increase the light transmittance of the crown and ensure fruit coloring.

3. Control the crown height

It is inconvenient to operate apple trees when the height exceeds 4 meters. It should generally be controlled at 2.5-3.0 meters to facilitate operations such as flower thinning, fruit thinning, and bagging.

4. Adjust the spacing between rows and plants

For orchards with too small row spacing, the long branches between rows should be thinned out, the distance between plants and branches between rows should be kept at 1.5-2.0 meters, and the lighting conditions should be improved.

5. Control the total number of branches

Appropriately reduce the number of branches, and control the number of branches per mu to about 60,000 to ensure fruit quality and yield.

3. Simplify pruning methods

1. Reduce stubs

Except for shortening young trees, shortening is basically not done in other cases to avoid stimulating the growth of vigorous branches.

2. No retraction pruning

Avoid the annual pruning method and instead use the method of completely thinning out overcrowded branches.

3. Long-term release

Branches that are considered useful should be left long to form a single-axis, slender, oblique, drooping, loose branch group.

4. Thinning

Clear the densely grown areas or branches on the entire tree and maintain appropriate distance between branches.

5. Pull the branches into place

Use the strong branches on the back to pull the branches until their heads are facing downward; pull the lateral branches on the upper part of the central leading trunk to 110-120° to control the expansion of the crown and promote fruit growth.

In short, a simplified pruning method is used, and pruning is carried out in branch groups. The fruit branches are not headed, and only the overly dense branches are thinned out, leaving a large number of flowers. Adjust thinning during flowering period to ensure stable yield year after year.