In order to obtain apples that are well-colored, it is necessary to keep an eye on them, so that the crowns in densely planted orchards are narrower at the top, a wider bottom. The tendency to grow is often the opposite. Crowns grow more strongly at the top than at the bottom and their shape must be corrected by cutting.
Even a very intensive cutting is not able to stop the process of the deterioration of the color of apples as the apple grows older. The difficulty is there, that older apple trees, after winter and spring pruning, produce very large amounts of vigorously growing shoots, commonly known as wolves. For example, on the 15-year-old apple trees of the Bankroft variety, you can count on average approx 100 wolves with a total length 60 m. In summer, they shade the fruit, reducing the penetration of light into the crown by half.
Summer cutting, consisting in removing wolves and other vigorously growing shoots from the crown improves the color of apples most effectively. Such a cut should be made at least 4 weeks before the expected fruit harvest date. On trees of early varieties, they must be done at the beginning of July, and late varieties in the first half of August.
Adequate sunlight on all the twigs in the crown plays an important role not only in the cultivation of apple trees, in which the blush on the fruit arises only when exposed to direct light. In stone fruit, plum, blush cherries can develop even when the light does not reach the fruit directly. However, light is necessary for the fruit to mature evenly, for the accumulation of an appropriate amount of sugars in them, acids and other compounds, which determine their nutritional value and taste. For example, in excessively condensed cherry crowns, shaded fruits ripen 2-3 weeks later than sunlit fruits outside.
Cutting, regulating the light conditions inside the crowns, influences the chemical composition of the fruit and its ability to store. High insolation promotes the accumulation of sugars in the fruit and an increase in the dry matter content.
Cutting, improving the sun exposure of the crowns, changes the storage capacity of the fruit. Fruits grown in well-sunlit crowns have more skin defects in the form of microcracks invisible to the naked eye. After being put in storage, they are more susceptible to fungal diseases than fruit from dense crowns, little sun. Minor damage to the rind facilitates the infection of pathogenic fungi. The fruits of cut trees are larger and more mature, therefore they wilt faster in storage than fruit from uncut and dense trees. The latter, on the other hand, are more easily affected by some physiological storage diseases, such as internal disintegration and joint browning..