Cultivating appropriate tree shape and correctly handling the relationship between nutrient growth and reproductive growth of blueberry plants are extremely important technical means and measures to ensure that large-fruited blueberry cultivation obtains the best balanced yield and optimal quality. The Berry Research Institute of Heilongjiang Academy of Agricultural Sciences and Yichun Agricultural Technology Research and Promotion Center of Heilongjiang Province adopt the non-stem type shaping and pruning and fixing branch, fixing fruit, directional cultivation and management technology, which perfectly combines the quality management of fruit with shaping and pruning and fruit thinning, so that the blueberry products are good in appearance, high in quality, and consistent in ripening, which meets the market demand and improves the economic benefits. Half-high bush
North high bush tree shape to no main stem multi-primary branch bush round head shape, umbrella shape is mainly suitable for cold land blueberry orchards. Plastic pruning first of all, the specific tree shape specification, retain robust fruiting main branches 5-7, side branches 30-40, 25-30 fruiting branch groups. Each fruiting branch group retains 15-20 flower buds, and 20-30 fixed fruits.
(1) Young trees: young trees 2-3 years old should be planted, and the stem should be set at 15-20cm in the year of planting, and after planting, 3-5 new shoots in different directions with even distribution should be left as main branches. In the second year, thin out the weak branches, mainly to expand the crown, wipe out all the flower buds to prevent flowering and fruiting, and promote strong branches. For good field management, vigorous growth of young trees, when the upper branches of the plant has formed a better crown, and the lower or middle of the original auxiliary branches due to the lack of sufficient sunlight, affecting the ventilation and light, it should be removed in a timely manner. The young tree is about to enter the fruiting season mainly to remove the lower weak branches, drooping branches, horizontal branches and the crown of the cross branches, overcrowded branches, overlapping branches, but also through a light short cut, remove the flower buds at the top of the branch. If the amount of flower buds is a lot, cut the flower buds on the size of the crown has a greater impact, you can also erase the flower buds, in order to facilitate the expansion of the crown. After the flower buds are removed, some secondary buds on either side of the flower buds will sprout and draw branches. When cutting branches short, the remaining branches should be long and short, staggered, so that the new shoots below the cut can reasonably occupy their own space. Due to the light pruning, the new plants produced in the spring tend to be more in number, the growth potential is relatively weak, and the new shoots are overcrowded. In order to prevent this phenomenon, young trees sprouting in the spring, should be selected as early as possible to erase some of the new shoots, to strengthen the new shoots of the remaining growth potential, so that the crown as soon as possible to the periphery and the development of high places.
(2) Mature trees: into the fruiting season, the size of the tree crown has basically reached the requirements, should begin to control the further expansion of the crown, and the limited space for the more vigorous growth of the branches or branches. At this time, the tree is more open varieties, thinning to weak and strong. Upright varieties to the center of the trunk, open the skylight, leaving mediocre branches. Weak branches can be used to wipe the flower buds method of pruning, so that the transfer. The amount of flower buds of mature trees, often using the method of cutting flower buds to remove part of the flower buds, generally each strong branch cut 2-3 flower buds. Pruning to thinning mainly, thinning out the tree everywhere in the dense branches, weak branches, insect branches, wounded branches, dead branches, cross branches, close to the overlap of the branches, old branches, as well as root tillers. Due to retraction or results and weakened and replaced by new branches of the dominant branch group, systematic retraction of large branches. Big branch retraction can be first light and then heavy, that is, the first retraction 1/3-1/2, until after the retraction of the renewed big branches weakened again, you can increase the retraction strength, cut off 2/3, or even from near the ground to cut off. If the branch senescence is more serious, then you can thin out the big branches from the root to make way for the newborn big branches with strong growth potential. Cultivate 1-3 year-old fruiting reserve branch groups and leave 4-5 year-old fruiting branch groups. Using this year by year batch renewal method, than the whole plant senescence after a one-time renewal is better, so that can slow down the fruit tree senescence, but not loss of yield. The weakening of branch groups and large branches is relative, and there is no absolute standard. Whether you need to thin or retract depends on whether you can meet the ventilation and light conditions of the tree, and which branch or group of branches or big branches to thin or retract depends on which growth is the weakest. The only criterion is to remove the weak and leave the strong. In addition, there is no fixed boundary between plants, the space they occupy in the orchard is not necessarily equal, if necessary, the strong plants can be made to occupy more space, that is to say, you can support the strong and remove the weak. For adult trees, removing the weak and leaving the strong should be understood dialectically. When some of the stronger branches affect neighboring plants, it is better to keep the relatively strong branches or median branches. Although strong branches produce more fruit, they occupy more space. When there is no shortage of branches on an adult tree, it is better to remove the strongest branch and keep the middle branch if the presence of a large branch disturbs the shape of the tree. Of course, this is not very common, because there are not many overly strong branches on mature trees, and a few strong branches can usually be used to develop large branches to replace large, senescent branches. Generally speaking, plant yield should be controlled at 1.5-2kg.
(3) Old tree renewal: 12-25 years after planting, the above ground part of the tree will be senescent, at this time, the whole tree renewal, that is, the above ground part of the flat stubble with a brush cutter, stubble height of 2cm, the second year from the base of the resprouting of new branches, tree renewal and re-strengthening. After the whole tree renewal year does not bear fruit, the second year can blossom and bear fruit, the yield will be greatly increased.
In blueberry production practice, the large tree flat stubble method is almost not applied. In fact, in the early planting of blueberry gardens, due to poor management or soil improvement is not in place and other factors, tree aging phenomenon is very serious. Therefore, the use of flat stubble to realize the renewal and rejuvenation of the tree is an important means to guarantee the economic life of the tree and to improve the quantity and quality of the harvest. In New Zealand, flat-cropping is used once every seven years, doubling yields after three years.
Post time: Aug-22-2025