"King of melons" what kind of fertilizer should be used for watermelon? How to apply fertilizer in each growing period? How much fertilizer does one mu of land need?

Watermelon, also known as cold melon, summer melon, etc., is a common fruit in China in summer. It is deeply loved by people because of its sweet flesh, cooling and dispelling summer heat, diuresis and so on. Whether watermelon is sweet depends not only on the variety, but also with fertilization, light and other factors, so what fertilizer is good for watermelon fertilization? How to apply fertilizer in each growing period? How much fertilizer does one mu of land need?

First, the law of fertilizer requirement of watermelon:

For every 1000 kg of watermelon, it needs 2.25kg of nitrogen, 0.9kg of phosphorus and 3.38kg of potassium (only refers to the mass of elements in the fertilizer, not 2.25kg of nitrogen and 0.9kg of phosphate, the same below). It is sensitive to trace elements such as boron, zinc, molybdenum, manganese and cobalt, and has certain requirements for calcium, magnesium, iron and copper.

What kind of fertilizer should be used?

On the basis of adequate application of mature organic fertilizer in medium fertility soil, 11 kg of potassium (equivalent to 22 kg of potassium sulfate), 11 kg of nitrogen (equivalent to 55 kg of ammonium sulfate or 24 kg of urea) and 5.7 kg of phosphorus (equivalent to 48 kg of calcium superphosphate) were applied per mu. Watermelon has good quality, high yield and good benefit. Or 45% organic fertilizer 40 kg / mu and 45% potassium sulfate compound fertilizer 70 kg / mu. 3050% of organic fertilizers and chemical fertilizers are used as base fertilizers and are applied before soil preparation. The rest is used as topdressing and used in different stages. In this way, the watermelon will be big and sweet. Jiayou organic fertilizer has been tested in the past two years, and the effect is remarkable. Its high nutrient content, good absorption, improve soil properties, and even improve plant disease resistance, leaf morbidity decreased, the most important thing is to improve the quality of watermelon, the fruit is smooth and glossy, a big sweet, thin flesh sand. The choice of watermelon fertilizer should avoid chlorine-containing fertilizer, such as ammonium chloride, potassium chloride, chlorine-containing compound fertilizer, especially in greenhouse watermelon fields. Because these fertilizers will make the melon taste lighter, salty, and extremely easy to rot fruit. In a word, if we want to grow watermelon well, we must make a reasonable combination of organic fertilizer and inorganic fertilizer, and a reasonable proportion of nitrogen, phosphorus, potassium and other elements. The application of inorganic fertilizer alone will harden the soil and reduce the quality of watermelons. Good watermelons need good fertilizer. I hope that the vast number of farmers can plant watermelons of high quality and amazing yield as soon as possible.

Third, fertilization skills:

1. Base fertilizer of watermelon

The requirement of watermelon on soil is not strict, but sandy loam is the best, which is beneficial to root development. The root system of watermelon grafted and replaced by root is more developed, and the soil should be turned 40 cm deep before planting to make the root system grow fully. Apply fully mature high-quality organic fertilizer 4000kg / mu, urea 15kg / mu, calcium superphosphate 25kg / mu, potassium sulfate 10kg / mu, or watermelon special fertilizer 50kg / mu, combined with deep ploughing and soil preparation, apply half of the fertilizer in cultivated land and the other half when ridging, and evenly mix chemical fertilizer and organic fertilizer with the soil in the ditch.

The specific amount of fertilizer application can be determined according to the local soil fertility and yield level, and in a certain range, the amount of fertilizer application increases with the increase of yield.

2. Topdressing of watermelon

The main results are as follows: (1) Watermelon fertilizer: when the normal young fruit grows to the size of the egg, the fruit begins to expand rapidly, and the fertilizer requirement of the plant gradually reaches the peak of the whole growth period. At this time, we should re-apply expanded melon fertilizer to promote melon expansion and prevent premature senility. The topdressing of watermelon is mainly based on phosphorus and potassium fertilizer, with little or no application of nitrogen fertilizer to avoid the decline of watermelon quality caused by excessive nitrogen fertilizer. Apply 15 kg of diammonium phosphate, 15 kg of potassium sulfate, 10 kg of urea, or 20 kg of special fertilizer for watermelon per mu. It is recommended that the planting net should be applied at a hole 30 cm away from the melon root beside the ridge, or between the two plants near the ditch. Timely watering the melon after fertilization can promote the absorption of nutrients and accelerate the expansion of the fruit.

(2) Restoration fertilizer for watermelon: immediately after the first harvest of watermelon, quick-acting chemical fertilizer was applied immediately, generally applying urea 15kg / mu, potassium sulfate 15kg / mu, diammonium phosphate 10kg / mu, combined with topdressing and watering once to supplement nutrients and water in the soil, maintain strong plant growth potential and prevent premature senescence of vine leaves.

(3) foliar fertilizer fertilization: foliar fertilizer spraying is a necessary means to make up for the deficiency of root absorption, supplement nutrition and balance nutrients for plants. it has the characteristics of low practical cost, uniform fertilization, fast fertilizer efficiency, high nutrient utilization rate and so on. Generally, starting from the expansion period of the first stubble of watermelon, spraying 0.3% 0.5% potassium dihydrogen phosphate or potassium treasure solution every 7-10 days can enhance the stress resistance of watermelon, increase the flowering rate and fruit sugar content, and increase the yield.

(4) carbon dioxide gas fertilizer: the application of carbon dioxide gas fertilizer in the fruiting period of watermelon can improve the photosynthetic intensity of leaves and prevent plant premature senescence, which is an important measure to increase sugar accumulation and yield of watermelon in greenhouse. At present, acid reaction fertilizer application method is often used in production. Put a plastic bucket every 50 cubic meters in the shed, add 6 liters of water per barrel, then slowly add 2 kilograms of industrial sulfuric acid and mix it evenly with water. At about 9 o'clock every day, 250 million 400 grams of ammonium bicarbonate fertilizer will be wrapped in plastic bags, pierced a few holes, and put into the bucket to slowly release ammonium bicarbonate into dilute acid solution, resulting in carbon dioxide gas, so that the concentration of carbon dioxide in the shed is increased to about 1000 mg / kg. The ammonium sulfate solution produced by the reaction can be diluted 300 times as a nitrogen fertilizer and applied to the melon field with watering.

3. Key points of fertilization technology:

The main results are as follows: (1) when applying farm fertilizer in soil preparation, more farm manure with complete components, such as chicken manure and sheep manure, were applied to produce watermelons with neat size, good flavor and high sweetness.

(2) "Manyuanchun" microbial agent containing potassium bacteria, biological organic fertilizer and black plus white biological fertilizer are compound high-tech microbial fertilizers, which are applied in the whole growth period of watermelon. it can make the watermelon leaf color dark green, fruit shape correct, sweetness increased by 1 to 1.5 degrees.

(3) apply stevia 500 grams of stevia, 10 grams of soybeans, add 25 kilograms of water, bubble and boil until dry. When the watermelon blossoms and sits, the hole is applied 13 cm away from the seedling, with a depth of about 13 cm, so that the melon is large and sweet.

(4) spray boron calcium solution method sodium borate 150g, calcium chloride 50g, sucrose 1000 g, add 100kg water fully dissolve, spray in the afternoon of sunny day during watermelon expansion period, can increase sweetness by 20%.

(5) spraying rare earth method watermelon at true leaf stage, first flowering stage and expansion stage, spraying 0.05%, 0.06% and 0.08% rare earth nitrate solution 75 to 100 kg respectively, the sweetness can be increased by 0.6 to 0.7 degrees.