Technical Management of Grape Blossom Period
Grapes, as an economic crop among vine fruit trees, their blossom period management directly affects the annual yield and fruit quality. From flower spike differentiation to fruit setting, a crucial growth period of about 30 days requires meticulous management. Scientific blossom care not only improves the fruit setting rate but also lays the foundation for subsequent fruit development. The following will elaborate on key operations from four dimensions.
I. Nutrient Supply Management
1.1 Prime Time for Pre-Flowering Fertilization
Apply high-phosphorus compound fertilizer (N-P-K=15-30-15) 7-10 days before flowering, with an amount controlled at 20-25 kilograms per mu. Combine with a drip irrigation system to apply humic acid water-soluble fertilizer to promote flower organ development. When foliar spraying a 0.2% boric acid solution, avoid the high-temperature period at noon, and it is recommended to finish before 10 a.m.
1.2 Post-Flowering Fertilization Strategy
Immediately replenish calcium and magnesium elements after the flowers fade, applying 50g of calcium magnesium nitrate fertilizer per plant. Reduce the proportion of nitrogen fertilizer at this time to avoid excessive growth of branches, and use a balanced water-soluble fertilizer (20-20-20) for flushing.
II. Environmental Control System
2.1 Precise Temperature and Humidity Control
Greenhouse cultivation requires maintaining a day temperature of 28±2°C and a night temperature of 16-18°C. Install temperature and humidity sensors for real-time monitoring, and when the relative humidity exceeds 65%, open the top vent for ventilation. For field-grown grapes, till the soil to reduce humidity, maintaining soil moisture content between 60-70%.
III. Flower and Fruit Optimization Plan
3.1 Scientific Flower Thinning Technique
Retain 2 inflorescences on strong fruiting branches, 1 on medium-strong branches, and remove all on weak branches. During operation, retain the top 3-5 cm of the spike, removing the secondary spike and the shoulder. For the Juefeng series, this should be completed 3 days before flowering, while for varieties like Hongdiqi, it can be extended to the early flowering stage.
IV. Pollination Assurance Measures
4.1 Artificial Auxiliary Pollination
During the full bloom period (when 60% of the flowers are open) from 9-11 a.m., use an electric pollination device to vibrate the fruiting branches. For female flowers, collect pollen from male flowers in advance and use a brush application method, repeating the operation every 48 hours.
Through systematic blossom period management, the fruit setting rate can be increased by over 30%. Growers need to adjust flexibly based on the characteristics of the variety and climatic conditions, combining digital monitoring equipment to achieve precise agricultural operations, laying a solid foundation for grape yield and quality.