How to Fertilize Greenhouse Watermelons
For netizens who are concerned, this article provides a detailed explanation of how to fertilize greenhouse watermelons and the knowledge about the care methods for fertilizing and maintaining greenhouse watermelons. Next, the editor will provide you with a detailed answer.
Watermelons are the fruit of summer, with sweet flesh that can cool down and eliminate heat; the seeds contain oil and can be used as a snack; the rind is medicinal and has the effects of clearing heat, diuresis, and lowering blood pressure. It is rich in vitamins, and many farmers grow watermelons in greenhouses. Watermelons prefer warm and dry climates and are not very cold-tolerant. If you want to grow good watermelons, you need to pay attention to fertilizing them. Below, we will introduce the fertilization methods for greenhouse watermelons from six aspects: vine elongation fertilizer, fruit expansion fertilizer, rejuvenation fertilizer, foliar fertilizer, fertilizer requirements, and key points of fertilization techniques.
1. Vine Elongation Fertilizer
When watermelons enter the vine elongation stage, the demand for water and fertilizer increases. At this time, we need to apply top dressing in a timely manner to promote the growth of the melon vines and expand the leaf area. Top dressing usually consists of humic acid organic fertilizer, which can be appropriately combined with a moderate amount of water-soluble fertilizer. Generally, each mu requires 450 kilograms of organic fertilizer and 60 kilograms of high-efficiency nitrogen-phosphorus-potassium compound fertilizer, and watering can follow the "dry-wet" principle.
2. Fruit Expansion Fertilizer
When watermelons grow to the size of an egg, it is the period with the highest fertilizer requirement. During this period, timely fertilization is needed to ensure the growth of the watermelon fruit. A heavy application of fruit expansion fertilizer is required to promote the expansion of the melon and prevent premature aging. Fruit expansion fertilizer usually consists of phosphorus and potassium fertilizers, with a small amount of nitrogen fertilizer needed. Excessive nitrogen fertilizer can lead to a decrease in the quality of watermelons. Each mu requires 15 kilograms of high-potassium type冲施肥, which can promote the absorption of nutrients by watermelons and accelerate fruit expansion.
3. Rejuvenation Fertilizer
After the first crop of watermelons is harvested, it is necessary to apply a quick-acting fertilizer immediately. Generally, each mu will use 15-20 kilograms of urea, 10-15 kilograms of potassium sulfate, and 8-12 kilograms of diammonium phosphate, which can supplement the nutrients in the soil, maintain the rapid growth of watermelons, and prevent the early aging of vines.
4. Foliar Fertilizer
Foliar fertilization is a supplement for plants to absorb nutrients, thus compensating for the insufficiency of root absorption. Starting from the first fruit expansion period of watermelons, it is necessary to spray foliar fertilizer every 7-14 days, using a 0.3%-0.5% solution of potassium dihydrogen phosphate.
5. Fertilizer Requirements
Research shows that watermelons with a yield of 3500 kilograms per mu need to absorb 10.5-11 kilograms of nitrogen, 3.5-4 kilograms of potassium, and about 11.5 kilograms of potassium. Because watermelons grow relatively fast, their fertilizer requirements are also relatively high. When growing watermelons, it is important to note that the nutrient absorption of watermelons in the seedling stage is relatively low, so the amount of fertilizer can be reduced appropriately, accounting for about 0.55% of the total requirement. During the vine elongation stage, their growth rate is faster, accounting for about 14.6%. In the fruiting stage, the fertilizer requirement is the highest throughout the growth period, accounting for 84.85%. Therefore, when fertilizing, it is necessary to strictly follow the ratio.
6. Key Points of Fertilization Techniques
It is recommended to use nutrient-rich soil with high organic matter content when seedlings are grown, while also ensuring that the soil is loose and has good water and moisture retention. A heavy application of base fertilizer can ensure a high yield of watermelons. Therefore, after the harvest of the previous crop, the soil should be combined with deep tillage and 4000 kilograms of decomposed organic fertilizer should be applied per mu.
The above introduction on how to fertilize greenhouse watermelons and detailed explanation of the fertilization and maintenance methods for greenhouse watermelons are hoped to provide some floral knowledge for green plant enthusiasts.