Watermelon is a fertile crop with short growth period, but it needs a large amount of fertilizer. The whole growth period absorbs the most potassium, followed by nitrogen and phosphorus. The absorption of NPK is different in different growth stages of watermelon.
Fertilizer rule
1. The seedling stage watermelon is from the true leaf to the 5 true leaf stage (group period), about 30 days. In this period, the vegetative growth is small, and the absorption of NPK is less, which is the slow absorption stage of fertilizer.
2, the extension of the vine period from the "group" to the first female flower is open, about 15-20 days, the watermelon section is rapidly elongated, the leaf area is enlarged, the root system is basically formed, the absorption capacity is enhanced, and it is the progressive absorption stage of the fertilizer. It absorbs more nitrogen, less potassium and less phosphorus.
3. The flowering result period is from the first flowering of the melon to the fruit ripening, about 30-40 days. In this period, the vegetative growth and reproductive growth of the watermelon are vigorously carried out, and the vegetative growth is mainly turned to reproductive growth, which is the fertilizer. The rapid absorption stage is the peak of fertilizer demand for watermelon. The absorption of NPK is about 85% of the total amount, and the most uptake during the expansion period is about 75%, and the potassium is the most in the flowering stage.
High-yield cultivation and fertilization technology of watermelon
1. Fertilization principle
(1) Organic fertilizer is the main factor, supplemented by chemical fertilizer. The addition of organic fertilizer can not only improve the soil structure, supply comprehensive nutrition, but also increase the sweetness of watermelon to improve the quality of watermelon.
(2) Apply nitrogen fertilizer, reapply potassium fertilizer, and apply micro-fertilizer. Nitrogen is an essential element for the growth of watermelon, but the amount of nitrogen applied is too much, stems and leaves are vigorously grown, stems are thick, leaves are enlarged, stems and leaves are overlapped, photosynthesis is weakened, vegetative growth and reproductive growth are imbalanced, resulting in poor fruit setting and affecting watermelon yield. Nitrogen should be used in an appropriate amount. Potassium is the most important element in watermelon life. Potassium can promote the transportation of photosynthetic products and improve the yield and quality of watermelon. Therefore, it is more important to increase the application of potassium fertilizer in watermelon.
(3) According to the different growth stages and growth of watermelon, soil and climatic conditions, timely and appropriate fertilization.
2. Fertilization technology
(1) The application of base fertilizer generally accounts for 70% of the total fertilization amount of watermelon, mainly based on organic fertilizer, and is applied with appropriate fertilizer. For soils with moderate fertility, about 4 000 kg of organic fertilizer per mu, 15 kg of urea, 15 kg of diammonium phosphate and 25 kg of potassium sulfate. Organic fertilizer preparation, when the ploughing is 2/3, the application of sputum, 1/3 and commercial fertilizers are drenched into the pond and concentrated into the ridge.
(2) Application of top dressing Watermelon topdressing should master the principle of light application of seedling fertilizer, skillful application of vine fertilizer, and heavy application of squash fertilizer.
1 Miao fertilizer: According to the growth of seedlings and soil conditions, the number of topdressing and topdressing can be determined. The soil is fertile, the amount of base fertilizer is large, the seedlings grow robustly, and they can not be chased, or topdressing once in 3-4 true leaves. Urea 10 kg.
2 vine season: watermelon needs fertilizer gradually increase, according to the growth of topdressing, generally when the vine grows to 40-50 cm, combined with watering per acre of urea 15-20 kg, potassium sulphate 10-15 kg or High-nitrogen compound fertilizer 20-25 kg to promote the growth of melons. The use of nitrogen fertilizer is sufficient for the base fertilizer and the application of the seedling fertilizer. Stretching the vines should be applied early, and the vines are generally no longer topdressed in the middle and late stages, so as to prevent the watermelon from growing too much and affecting the sitting.
3 Expanded melon period: The expanded melon period is the peak period of watermelon in the whole life, and it is also the key period of topdressing. The expanded melon fertilizer can promote fruit expansion and increase watermelon yield. Phosphorus and potassium fertilizers are mainly used, and nitrogen fertilizer is appropriately controlled. The dosage accounts for 50% of the total amount of topdressing, and is applied twice. 4-5 days after Xiehua, the size of the fruit egg, 25 kg of potassium sulfate, 15 kg of diammonium phosphate, 5 kg of urea, 15 days after Xiehua, the size of the fruit bowl, chasing the 2nd expanded melon, per acre Apply 15-20 kg of diammonium phosphate, 10-15 kg of potassium sulfate, and apply water to the hole.
4 external top dressing: If there is browning and premature aging in the late growth stage of watermelon, 0.20%-0.30% potassium dihydrogen phosphate or 0.30%-0.40% fertilization can be sprayed on the foliar surface to quickly supplement nutrition.
This article URL: The fertilizer requirement and high-yield skills of watermelon
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