**I. Soil Improvement in Pollution-Free Orchards**
1. **Deep Tilling and Soil Loosening**: Deep tilling is one of the most fundamental practices for improving soil quality in orchards. By deeply tilling the soil, its physical and chemical properties are enhanced, microbial activity is stimulated, organic matter decomposition is accelerated, and soil degradation is reduced. This helps improve nutrient availability, promoting better root development and nutrient uptake by fruit trees.
The best time to perform deep tilling is after harvest in autumn, before the tree enters dormancy, and can be combined with the application of base fertilizer and straw. It can also be done early in spring once the soil thaws. The ideal depth for tilling is around 60 cm, depending on the root system distribution. To maintain soil health, it’s recommended to alternate between deep tilling and soil loosening every other year, or use a full-park deep tilling approach.
2. **Cultivation During the Growing Season**: In the growing season, after rainfall or irrigation, it's important to loosen the soil promptly to control temperature and suppress weeds. Regular cultivation helps maintain good soil aeration and prevents weed competition.
3. **Grass Planting and Mulching**: In suitable orchards, planting grass between trees can help improve soil structure and moisture retention. Grasses should be short, low-growing, and resistant to trampling, with minimal water needs and no common pests or diseases that affect pears. Ideal species include dwarf green manure crops like alfalfa, clover, vetch, and legumes such as peas, beans, and lentils.
Grass planting is best done in spring or autumn using either live plants or transplanting methods. Alternatively, mulching with crop residues, green manures, or weeds (cut into 15–30 cm lengths) can be applied under the tree canopy or between rows, with a thickness of about 10 cm. Dry materials should be soaked before covering to prevent fire hazards.
**II. Fertilization Management in Pollution-Free Orchards**
1. **Fertilization Principles**: Organic fertilizers should be the main source of nutrients, with chemical fertilizers used only as a supplement. Base fertilizers are essential, while topdressing should be applied according to the tree's growth stage. It is important to avoid using untreated municipal waste, nitrate-based fertilizers, unverified manure, or unregistered fertilizer products.
2. **Fertilization Methods**: The best time to apply base fertilizer is after the autumn harvest, combined with deep tilling. Organic fertilizers should be placed in the root zone, where they decompose slowly, helping to balance soil temperature and moisture, and support root development. A typical rate is 4–5 m² of organic fertilizer per acre, mixed with a small amount of mineral fertilizer.
Topdressing should be done in three stages:
- **First Application (Before Bud Break)**: Mainly nitrogen, with some phosphorus and potassium to support flowering and new growth.
- **Second Application (During Flowering and Fruit Set)**: Focus on nitrogen and phosphorus to reduce fruit drop and promote leaf growth.
- **Third Application (During Fruit Expansion)**: Emphasize nitrogen and potassium to improve fruit quality, enhance stress resistance, and encourage flower bud formation.
If deficiencies occur, such as iron or zinc deficiency causing yellow leaves or leaf curl, foliar sprays containing these elements should be applied. Mixing them with organic material improves their effectiveness.
3. **Foliar Spraying**: Leaf spraying should be done 4–5 times a year, with 2–3 applications during the growing season focusing on phosphorus and potassium, and trace elements. Common concentrations include:
- Urea: 0.3%–0.5%
- Potassium dihydrogen phosphate: 0.2%–0.3%
- Borax: 0.1%–0.3%
- Ferrous sulfate: 0.1%–0.4%
- Zinc sulfate: 0.1%–0.2%
**III. Orchard Irrigation**
1. **Irrigation Principles**: The water used for irrigation must meet pollution-free agricultural standards. Untreated sewage or contaminated water is strictly prohibited.
2. **Irrigation Methods**: Irrigation should be done 3–4 times a year, including:
- Before flower buds open
- During fruit set
- During fruit enlargement (if rainfall is insufficient, flood prevention measures may be needed)
- After harvest, combined with base fertilizer application
Pears should be watered 20 days before harvest. Drip or micro-irrigation systems are recommended where feasible to ensure efficient water use and minimize waste.
CHANGZHOU RICHGENIUS MEDLAB CO.,LTD , https://www.rich-gen.com