According to the experiment of the research group of big cherry greenhouse cultivation in Hebei Vocational and Technical Teachers College, it is suggested that the big cherry tree in greenhouse or greenhouse should adopt a single-layer small crown shape. Single-layer crown can be divided into no main branches, and it is only necessary to cultivate enough long branches (6 ~ 15) on the main branches according to the row spacing of plants and the space in greenhouse or greenhouse. Therefore, the heights of the trunk, central trunk and branch group of the single-layer small crown tree (as shown in Figure 14) are determined only according to the height of the plastic film.
Figure 14 Schematic diagram of single-layer small crown structure
Cultivation process of single-layer small crown tree;
(1) dingan
The fixed dry height of single-layer crown tree is generally 45 ~ 50 cm. If the fixed stem is too high, the central stem length of the branch group will be too short, which will reduce the number of upper branch groups on the main stem. Too low fixed stem will cause the lower branches to droop and mop the floor after the results. After drying, 3 ~ 4 primary buds can grow under the cuttings. When the length of the primary branch is 30 ~ 40 cm, coring is carried out, and after coring, 2 ~ 3 secondary branches can be extracted from the top of each new branch. In this way, each tree can form 6 ~ 12 branches in the same year. From late August to mid-September of that year, except for 1 central tip as the extension branch of the central trunk, all the lower branches (first-class tips) were pulled to an angle of 80 degrees. One of the secondary branches on each primary branch is left as an extension branch, and the rest are taken to increase the included angle with the mother branch or droop.
(2) winter pruning in the year of planting
In order to increase the number of branches and buds of trees and alleviate the growth potential of young trees, the pruning amount of cherry trees in the year of planting is very small. Generally, only the extension branches of the central trunk are appropriately cut short, and the rest branches are lengthened. The shortening degree of the extension branches of the central trunk should depend on the number of lower branches. If there are three small main branches in the lower part of a year, the extended branches can be kept about 40 ~ 50 cm during short cutting; There are two or one small main branches in the lower part, and only 20 ~ 30 cm is left after the elongated branches are cut short.
(3) Management of the growing season in the second year
In the second growing season, the management of aboveground parts of trees is mainly to control the overgrown branches on the back of the lower branches, and then take new branches from the branches and extended branches of the central trunk.
Last autumn, the long branch group was close to the level. On the back of the middle and rear branches, it is easy to grow clustered new buds. When the new bud grows to about 20 cm, twist it from the base of the new bud 2 ~ 4 cm to make it horizontal or drooping.
Generally, 3 ~ 5 strong new shoots can be produced under the cutting mouth of the extension branch of the central trunk, and the core will be picked when the new shoots grow to 30 ~ 40 cm. When the new branches are 30 ~ 40 cm long after coring, except one branch for extension, take other branches or twist them into a horizontal or drooping state, and pull them from late August to early September.
The winter pruning and growing season management in the second to third years shall be carried out with reference to the above, that is, only the branches extending from the central trunk shall be shortened and the remaining branches shall be lengthened in winter pruning every year; The management of the growing season is mainly to control the new shoots on the back of the flattened branches and the new shoots under the incision of the extended branches of the central trunk.
After 3 ~ 4 years of tree cultivation, the trees have generally reached their proper height (the cutting mouth of the last extension branch of the central trunk is kept at 50 ~ 80 cm from the surface of the greenhouse or greenhouse). At this time, pull the top branch to keep all the quilts almost horizontal.
It should be noted that the height of trees in different parts of the greenhouse or greenhouse is different from the ground, so the height of trees in different parts should be different, and the cultivation height of trees should be determined according to different specific conditions.