Detailed Guide to Blueberry Orchard Site Selection and Planting Methods
Blueberry Orchard Site Selection Methods
The soil pH at the orchard site should be 4 to 5.5, with the optimal soil pH being 4.0 to 4.8. Soil organic matter content should be 8% to 12%, and at least no less than 5%. The soil should be loose, well aerated, moist but not waterlogged. If local rainfall is insufficient, an adequate water source is needed. To solve the problem of waterlogging in summer, the raised-bed row cultivation method can be used. After the orchard site is selected, deep plowing should be carried out 1 year before planting together with green manure incorporation, with a depth of 20 to 25 cm being appropriate, so as to plow deeply and allow the soil to mature. If there are many weeds, a herbicide can be sprayed 1 year in advance to kill the weeds. For soil types that do not meet blueberry requirements, soil improvement should be carried out before planting to facilitate blueberry growth.
Adjusting soil pH when it is too high Soil pH being too high is an important factor limiting blueberry cultivation. Too high a pH often causes iron deficiency chlorosis, poor growth, reduced yield, and even plant death. When the pH is greater than 5.5, sulfur powder or aluminum sulfate needs to be applied to lower the pH. Sulfur powder should be applied 1 year before planting or at least in the year of planting, but applying sulfur powder generally has no effect in the same year. For example, in dark brown forest soil, to lower the pH by 1 unit in a 15 cm thick soil layer per square meter, 130 g of sulfur powder is required, and its effect can last for more than 3 years. Other soil types can refer to this application rate. Spread the sulfur powder evenly over the entire orchard soil according to the calculated application rate, then deep plow 15 cm and mix thoroughly. If aluminum sulfate is applied, the amount used is 6 times that of sulfur powder. In addition, mixing acidic peat into the soil, applying acidic fertilizers, and covering with sawdust and rotten bark all help lower the pH. If sulfur powder and peat are used together, the effect is even better.
Adjusting soil pH when it is too low When the soil pH is lower than 4, excessive heavy metal elements cause toxicity, resulting in poor growth or even death of blueberries. At this time, the pH needs to be increased, commonly adjusted with lime. When the soil pH is 3.3, applying 8 t of lime per hectare can raise the pH to above 4 and increase yield by 20%. Improving soil structure and increasing organic matter When soil organic matter content is below 5%, because the soil is compacted and clayey, and blueberries have fibrous roots, root development is unfavorable, so organic matter or river sand needs to be added to improve the structure. Sawdust, peat, rotten bark, or decomposed moss are commonly used and mixed into the soil at planting.
Blueberry Planting Methods
(1) Planting time: Both spring planting and autumn planting are acceptable. Among them, autumn planting has a higher survival rate, while spring planting should be done early.
(2) Spacing between plants and rows: Rabbiteye blueberry commonly uses 2 m × 2 m or 1.5 m × 3 m; highbush blueberry uses 1.2 m × 2 m; lowbush blueberry uses (0.5 to 1) m × 1 m.
(3) Pollinator tree arrangement: Rabbiteye blueberry is not self-fruitful, so pollinator trees must be arranged, and highbush blueberry varieties can be selected. Highbush blueberry and lowbush blueberry have relatively high self-fruitfulness rates, but arranging pollinator trees can also improve fruit quality and yield. The arrangement method uses a 1:1 or 1:2 ratio of the main cultivar to the pollinator cultivar.