1. Patterns and Characteristics of Late Spring Frost Damage
As temperatures gradually rise, fruit trees begin to resume growth. At this stage, fruit trees are not very resistant to severe cold, especially sudden temperature drops, which can adversely affect their growth. Young fruit and flower buds have poor cold resistance and are prone to frost damage during the budding and flowering stages, often resulting in significant economic losses. Generally, prolonged low temperatures, rapid temperature drops, and large temperature fluctuations during late spring frost increase the severity of frost damage.
2. Preventive Measures for Late Spring Frost
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Watering to Reduce Soil Temperature: Watering to lower the soil temperature before the arrival of cold air can help prevent late spring frost. Pay attention to weather forecasts before and after fruit tree flowering to effectively avoid late spring frost, delaying flowering by 2 to 3 days.
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Smoke Fumigation: Ignite damp straw around the orchard perimeter, typically around 2-3 am on the day cold air arrives, to create a layer of smoke over the orchard. This method, commonly used and easy to implement, helps prevent frost damage.
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Spraying: Before late frost arrives, spray a 0.3% to 0.6% potassium dihydrogen phosphate solution on flowering fruit trees to enhance the cold resistance of flower buds. Spraying foliar fertilizer/plant antifreeze can also prevent frost and increase fruit set.
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Wind Protection: Establish windbreaks at windy locations in the orchard to reduce or prevent damage from late frost and other adverse weather conditions, reducing frost damage to fruit trees.
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Covering: Cover fruit trees with reed mats, grass curtains, or plastic sheets to block external cold air and retain ground heat, thereby reducing frost damage. This method is most suitable for low-growing or young orchards.
3. Remedial Measures After Late Spring Frost
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Foliar Fertilization: Since late spring frost generally does not damage leaves, timely spraying of potassium dihydrogen phosphate and other foliar fertilizers can provide nutrients, enhance leaf photosynthetic efficiency, and ensure the normal growth of fruit trees.
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Artificial Pollination: For flowers that have not been damaged by frost, conduct timely artificial pollination using collected pollen. Collect pollen in advance for this purpose.
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Enhanced Fertilization and Irrigation: Especially in low-lying areas severely affected by frost, promptly apply growth regulators like ABA and irrigate to promote fruit tree growth and preserve undamaged flowers and fruits.
These are the measures to prevent and remedy late spring frost damage in fruit trees. Late spring frost can have a significant impact on fruit trees, sometimes causing complete crop failure and substantial losses for farmers. To minimize losses, it is essential to implement the above measures to prevent late spring frost.
