What conditions are needed for growing blueberries? Detailed pruning techniques

Blueberry, also known as bog bilberry, bog whortleberry, dū shì, dū shì, diàn guǒ, and bog bilberry lingonberry, is a fruit with very high nutritional value, with effects such as preventing cranial nerve aging and strengthening the heart. Blueberries are mainly distributed in North America, Europe, Russia, and China's Heilongjiang Yichun and other areas. Let's learn below what conditions blueberry cultivation needs to meet? Attached pruning techniques.

I. What conditions does blueberry cultivation need to meet?

1. Site requirements

The site should be chosen in a flat place (slope ≤15°C). Blueberry is a strongly light-loving plant, the site should have sufficient light, with no tall trees or buildings and other shading objects nearby. The site vicinity requires an irrigation water source, drainage must be unobstructed, and the groundwater level should be maintained at 0.35-0.55 m.

Blueberries fear both waterlogging and drought, and need well-drained soil. If the soil moisture is too high, it needs to be drained in time, but when there is no rainfall for a short time and no irrigation is carried out, water stress will occur. A simple method to judge whether the soil drainage condition is good or poor is to dig a pit with a diameter of 20 cm and a depth of 20 cm in the planting ground, and observe the change of the water surface in the pit 24 hours after heavy rainfall. If the water surface does not change, it indicates poor drainage, and such a plot is not suitable for planting blueberries.

2. Climatic condition requirements

Highbush blueberries can generally resist low temperatures of -30 to -25°C; half-high blueberries can resist low temperatures of -38 to -35°C; lowbush blueberries can resist low temperatures above -40°C.

3. Soil condition requirements

Blueberries prefer acidic soil. The pH value of the soil at the site should be 4.5-5.5, the soil should be loose with good aeration, the optimal soil porosity should be greater than 50%, and it should have good water retention and good drainage.

The soil organic matter content should be 8%-12%, and at least should not be lower than 5%. But different varieties have slightly different soil requirements. Blueberry groups need relatively low soil organic matter content (1%-2%), and soil types range from sandy soil and clay loam to sandy clay loam. Southern highbush blueberries have higher requirements for soil drainage, and the soil organic matter content should be ≥3%.

The productivity and yield of a blueberry orchard depend on soil improvement carried out one year in advance before planting (including correcting soil element deficiencies, controlling weed growth, improving soil organic matter content, soil structure, and soil pH), so as to facilitate blueberry growth. If the above soil physical properties still cannot meet the blueberry planting requirements after improvement, another suitable place should be selected to establish the orchard.

4. Water source condition requirements

Blueberries are very sensitive to the pH of irrigation water and to chemical elements such as sodium, chloride, boron, and bicarbonates. Before planting, relevant testing should be carried out on the water quality of the irrigation water.

II. Blueberry pruning techniques

1. Young trees

Refers to trees moved into the field for 1-3 years. During this period, the blueberry tree's shape has not yet formed, the tree vigor is relatively weak, it does not have fruiting capacity, the branches are relatively thin and weak, the amount of branches and leaves is small, and there are many drooping branches and creeping branches. At this time, the tree should not be allowed to bear fruit, as fruiting damages the tree and affects the plant's rapid growth in size and height. Therefore, all flower buds of the plant during this period should be pruned off. For those with a relatively large amount of branches and leaves, all thin and weak branches, creeping branches, and branches in poor positions should be pruned off; for those with a relatively small amount of branches and leaves, on the premise of ensuring a certain amount of branches and leaves, creeping branches and thin and weak branches should be appropriately handled.

2. Middle-aged trees

Refers to trees moved into the field for 3-5 years. During this period, the blueberry tree has a small fruiting capacity, and it is a period when the blueberry tree grows relatively vigorously. This period is the best period for shaping the tree form and also the most critical period for constructing the blueberry tree form. When pruning, not only how to achieve rapid growth should be considered, but also how to improve the blueberry tree's fruiting capacity.

3. Mature trees

Refers to trees moved into the field for more than 5 years. During this period, the main task of the tree is fruiting, so the vegetative growth of the blueberry tree should be controlled to increase yield. Pruning of mature trees is very complex, and the most issues need to be considered. Not only the yield of the current year but also the yield of the following years should be considered; not only should the tree be made high-yielding, but also the tree's actual fruiting capacity and its impact on the following years should be considered.