Light Application of Base Fertilizer and Timely Topdressing for Increased Yield
In the North China region, where winter-heated plastic greenhouses are commonly used for cultivating 2-3 crops per year, the crucial seasons are autumn-winter and winter-spring. Due to the rich soil resulting from years of organic and chemical fertilizer input, it is advised to apply a light base fertilizer. Based on experience, for mature greenhouses of approximately 8 years, it is recommended to use around 50 kg/acre of chemical fertilizer as the base fertilizer for autumn-winter tomatoes. A potassium sulfate-based high-phosphorus compound fertilizer, such as 12-18-15, is ideal. For shorter greenhouse lifespans, more can be applied, with a maximum limit of 150 kg/acre. Additionally, for autumn-winter crops planted in September when the temperature is suitable for robust growth, organic fertilizer may be minimized or omitted from the base fertilizer. Organic fertilizer is better reserved for the winter-spring season to enhance soil temperature and ensure a bountiful yield, as the planting period for this season occurs in the cold winter.
Determine Topdressing Quantity Based on Fruit Cluster Numbers
To optimize yield, the focus of topdressing should be on the number of fruit clusters. For instance, if six fruit clusters are left, topdressing can be done three times when the 1st, 3rd, and 5th fruit clusters swell. If four fruit clusters are retained, topdressing can be performed twice when the 1st and 3rd fruit clusters swell. When the crop load is substantial, an additional topdressing can be considered. A potassium sulfate compound fertilizer, with a preferable formulation of high nitrogen, low phosphorus, and high potassium, such as 18-8-18, is recommended for topdressing. The application rate is 40-60 kg/acre per time. During low temperatures, incorporating organic matter, such as humic acid, is advisable to mitigate the impact of pure chemical fertilizers on soil temperature and root systems.
Maintain Soil Health for Comprehensive Nutrient Supply
Tomatoes require essential microelements such as calcium, magnesium, boron, zinc, and iron. Their supplementation should be approached through basal application, topdressing, and foliar spraying. For basal application, options include boron-zinc urea, calcium-magnesium phosphate, and green iron fertilizer. Topdressing can be done simultaneously with compound fertilizers, using boron-zinc urea, boron-zinc, and ammonium nitrate calcium. Foliar spraying can be performed 2-3 times using calcium-magnesium-boron, zinc suspension, liquid calcium, and rapid green, among other options. It is crucial to follow the recommended application rates to avoid adverse effects. Additionally, maintaining soil health with products like Kangdileide or beneficial microbial agents (both containing Bacillus subtilis) can effectively prevent soil-borne diseases. These can be used for soil conditioning or mixed with fine soil and applied to planting holes at a rate of 1-2 kg/acre.
Disease Prevention for Threefold Benefits
Bacterial diseases (leaf spot and stem necrosis), late blight, and gray mold are the three major diseases of autumn-winter tomatoes. Effective prevention is essential for ensuring crop yield and quality.
For bacterial leaf spot prevention, seed treatment is foundational, using bactericides such as Kaida 3000 (or Bacillus licheniformis, copper oxychloride, or copper nitrate fulvic acid). Bacterial stem necrosis is a soil-borne disease, and preventive measures include enhancing soil conditioning and increasing microbial fertilizer. Measures for root irrigation, root-soaking agents, and stimulants for root growth are the primary means, with root-soaking agents for leaf spot disease spraying the same agents as those used on leaves. The use of efficient foliar fertilizers containing seaweed extract, such as Kapuke, is recommended.
Late blight prevention can be achieved by spraying Batian, Yin Fali, or antiviral copper sulfate 10-15 days before the onset of disease symptoms. Sporadic occurrences can be controlled using fungicides (such as Anke, Frost Urea Cyanide, Mieduoke, etc.) first, followed by spraying Batian, Yin Fali, and other protective agents.
Gray mold is one of the key diseases during the flowering and fruiting period. The pathogen is a typical weak parasite that thrives in low temperatures, high humidity, and low light conditions, especially in areas where crops decay. Prevention measures include: 1) clearing decaying flowers, leaves, and other debris during farming operations; 2) using fungicides such as Captan, Hartswood fungus, and combining with mepanipyrim for better results, paying attention to calcium supplementation. 3) Adding gray mold prevention agents to the flower-spraying solution, such as Shijiale 1000 times (or Topsin 1000 times, copper oxychloride 500 times) for prophylactic purposes.
Note: In adverse environmental conditions, such as low light, low temperature, and high humidity in greenhouses, spraying may increase humidity and compromise the efficacy of disease prevention. Smoke bombs can be tried as an alternative.
Post time: Dec-25-2023