Detailed Explanation of Key Techniques for Growing Watermelons in Open Fields in Early Spring

AbstractSowing: First mix the seeds with Xin Gaozhi film dressing, then use a hotbed with agricultural film arched shed for seedling raising; in the later stage, more exposure and less covering are needed, and the film should be removed three days before transplanting. Fertilization: During the growing period, the fertilizer requirement is relatively large, so sufficient base fertilizer should be applied, and double-furrow fertilization can be carried out; during the vine extension stage, urea, human excrement and urine, etc. can be applied as topdressing; during the fruit-setting stage, excessive fertilizer and water are not suitable, and topdressing should be carried out when the young fruit is the size of an egg. Pest and disease control: Pay attention to controlling damping-off, fusarium wilt, anthracnose, aphids, yellow squash beetles, cutworms, red spiders, and other pests and diseases.

I. Sowing

Before sowing, you can choose to mix the seeds with Xin Gaozhi film dressing, which can reduce the incidence of underground pests and diseases, isolate pathogen infection, does not affect the seed germination and imbibition function, helps strengthen respiration intensity, and increases the seed germination rate. A hotbed with agricultural film arched shed can be used for seedling raising. In the middle and later stages of seedling raising, more exposure and less covering are needed, exposing during the day and covering at night. 3-5 days before transplanting, the film can be uncovered all day for hardening off the seedlings, which is beneficial for cultivating robust seedlings.

II. Apply Sufficient Base Fertilizer

1. During the watermelon growing period, the fertilizer requirement is relatively large, so sufficient base fertilizer should be applied before planting, which is beneficial for high quality, stable yield, and high yield of watermelon. Per mu, 1500-2000 kg of decomposed fertilizer and 25-30 kg of watermelon-specific compound fertilizer can be applied.

2. Double-furrow fertilization can be carried out. At the two ends of the bed surface, 30-40 cm apart in the middle, open 1 furrow each with a depth and width of 20-30 cm, then apply the prepared fertilizer into the two furrows, cover with about 5 cm of soil, and transplant the seedlings in the middle of the two fertilizer furrows.

3. Using this fertilization method will not burn the seedlings and can prevent excessive vegetative growth. An appropriate amount of Chuhuawang No. 3 can also be sprayed, which is beneficial for converting vegetative growth into reproductive nutrition, inhibiting excessive growth of the main shoot, promoting flower bud differentiation, improving pollen fertilization quality, and enabling the plant to bloom more and set more fruit.

III. Scientific Topdressing

1. Apply sufficient base fertilizer before planting. During the vine extension stage, only 3 kg of urea and 200 kg of human excrement and urine need to be applied as topdressing. Watermelon is relatively sensitive to water and fertilizer during the flowering and fruit-setting stage. If there is too much fertilizer and water at this time, it will lead to excessive plant nutrition, easily causing excessive vegetative growth, and is not conducive to fruit setting.

2. Therefore, when the young fruit is the size of an egg, an appropriate amount of topdressing can be applied, combined with spraying Zhuangguadiling, which is beneficial for thickening the fruit stalk, promoting rapid fruit development, and also ensuring no flower drop, no fruit cracking, no fruit drop, and no deformed fruit during the growing period. By the watermelon fruit-setting and expansion stage, the roots and stems have just extended into the two fertilization furrows. At this time, the soil nutrients are sufficient, which is beneficial for improving the quality and yield of watermelon.

IV. Pest and Disease Control

1. Damping-off: During the seedling stage, the seedbed should be ventilated and aired in time, and the amount of watering should be controlled.

2. Fusarium wilt and anthracnose: It is necessary to wait 4-5 years before planting again, do a good job of clearing furrows and draining waterlogging, and promptly remove diseased plants. You can also use 20% Shibaoling, 70% Dikson, 75% chlorothalonil wettable powder, etc. to spray separately for control.

3. Aphids, yellow squash beetles, cutworms, red spiders, etc.: Rogor, trichlorfon, dichlorvos, and carbofuran can be used to spray separately for control.