KGB sweet cherry formation from one to four years
Every gardener knows that cherries, like many trees, are prone to active growth both in height and in width. If you leave the seedling without pruning, in the first ten years it will grow, forming an unproductive, high crown. However, this problem can be solved by forming a tree using the KGB system. What is the peculiarity of this technique, as well as what varieties is suitable for this method and the specifics of formation, let's understand together.
What is KGB shaping?
Such a crown is well lit and ventilated. Literally, Kym Green Bush (KGB) translates Kim Greene's bush. This technique was presented recently and is better known as the Spanish or Australian bush.
A phased scheme for the formation of cherries according to the Spanish bush system:
The pattern of cherry formation according to the Australian bush system:a - the first year; b-the second year; in - the third year; g - fourth year
For undersized crowns such a formation is a real salvation. It solves the problem of obstructed air circulation, which leads to lower yields and the risk of developing diseases.
Important! Due to the fact that the height of the tree is small and the first row of branches is low, such forms are not suitable for plants cultivated in areas with frequent frosts.
The purpose of the KGB system is to obtain a tree of lower height - such as a "bush". This greatly simplifies the implementation of basic work that can be carried out without a ladder, including harvesting, pruning, etc. This means that you can save time and labor.
As a rule, cherries yield from the fourth year of life, and during the period of full fruiting it enters into the fifth or sixth year.
What cherries are suitable for the KGB method
This type of crown formation is not suitable for all varieties. It can be used only for those sweet cherries that bear fruit on bouquet branches. Suitable for seedlings on tall rootstocks.
Suitable varieties for the KGB method:
- Merton Premier;
For varieties on dwarf rootstocks and hybrids such as Regina, this method is not applicable.
Did you know? Sweet cherry serves as a raw material for food coloring. And the color is not red at all, but green.
Features and technology of formation
The meaning of such a formation is to get more branches by means of a certain pruning algorithm during the first three years after planting a seedling in order to eventually get a bush (bowl) with 8-12 small branches that are then allowed to grow naturally. As a rule, cherries yield from the fourth year of life, and during the period of full fruiting it enters into the fifth or sixth year.
Video: KGB sweet cherry formation
In the first year of planting
During the opening of the buds, young trees are pruned at a height of 30–75 cm. This indicator depends on the height at which it is planned to form the main powerful branches, as well as on the presence of buds on the main conductor. Shoots developing from the kidneys (usually only 4) are pulled out and fixed to obtain large divergence angles. With proper care, the shoots grow rapidly and reach a size of 50-60 cm.
Important! Such a procedure requires varieties prone to the formation of highly growing branches.
In the summer, such branches are cut 15 cm above the cut of the main conductor. This is the last operation that is performed in the first year of growth. All emerging branches are cut at the same level from the soil surface.
By the end of summer, shoots of the second level grow to 50-60 cm. In the fall, parallel trellises are pulled along the plantings.Branches of the second tier are attached to them to obtain, in the future, even distribution of branches and an open crown. The shoots remain tied until the end of next spring.
Two year old sweet cherry
When new branches grow to 50-60 cm, they are shortened in the second year, leaving 25 cm from the base. This operation is performed in the spring, in the flowering phase. If the trees are undersized, it is better to wait until the branches have reached the desired length and only after that carry out pruning. In this case, the basic principle of shortening will be preserved.
Before preparing for winter, late autumn, branches of the third order grow to 60 cm. They are reduced at the same point as the branches of the second tier - about 25 cm from the base. This principle does not apply to all branches: growing in the center of the branched part and central horizontal branches do not cut.
Making shortening of the shoots according to the above scheme, a crown similar to a bush is obtained. Those branches that were not affected will begin to bear fruit in the near future. And they are left for the time being until the tree enters the active phase of fruiting.
In some cases, in the second season of growth, a tree may need to trim several branches to improve the illumination of the crown. First of all, strong horizontal branches are cut.
Important! Before the fruiting phase, the amount of fertilizer for such trees is limited. Feeding is resumed after the young shoots stop growing (they do not grow longer than 60 cm).
Three year old sweet cherry
In general, crown formation is completed in the second year of tree vegetation. From the third year of life, the crown in the upper part begins to thicken. Therefore, during this period, they begin to shorten the branches of the third tier - they leave 1-2 strong lower branches, and the rest are cut off. Similarly form the third level, which is spaced 30-40 cm from the second.
Young branches growing inward completely cut. The best option is that all the remaining branches should be directed up and to the sides, forming an angle with the main trunk of no more than 45 °. In the future, the task of the gardener is only to maintain the branched part in equilibrium and given dimensions (not higher than 2.5 m).
Did you know? Cherry is popularly called "bird cherry". This name is given because of the love of birds for sweet berries.
The formation of sweet cherries in the fourth year
For the fourth season, the trunk is brought to the level of young frame branches located on the sides of the crown. The third level of shoots is cut 15–20 cm below the top, but in the end the branches should not be longer than 0.7 m. If the branches of the second level are longer, pruning is not required. Subsequent manipulations performed in the spring consist of trimming branches growing inward of the crown or upward at a right angle.
It would seem that the trimming method is not of primary importance. But the KGB system allows you to get a beautiful, healthy tree in the garden, from which it will harvest easily and without loss.