The technique of growing watermelon with large fruit

I. selection of sites

1. Soil quality: choose sandy land with loose soil and good air permeability. Black land with about 30-40% sand content is the best. Clayey soil to increase the number of ploughing, improve soil permeability, it is best to turn the land in autumn. Do not plough the melon vine above 30cm to prevent root damage.

2. Topography: flat, slightly overtopped, sunny leeward, convenient for drainage and irrigation, no waterlogging (not urine Kang land), land close to water source, easy to manage, convenient for transportation.

3. Stubble: raw wasteland or second wasteland is the best, including grain stubble, wheat stubble, corn stubble, sorghum stubble, millet stubble and rice stubble. No watermelons, melons or vegetables should be planted for at least 6-7 years. Planting melons in rice stubble must be turned deep in autumn the year before last to ripen the soil.

II. Fertilization

The fertilization of watermelon is mainly based on base fertilizer, and the fertility (nutrients) is balanced, which is beneficial to improve disease resistance and stress resistance. Therefore, each mu should apply 5000 kilograms of fully mature high-quality farm manure (preferably sheep manure, chicken manure and pig manure. Horse dung, cow dung can also), calcium superphosphate (stone) 50 kg, three-element compound fertilizer 30 kg (or diammonium phosphate 20 kg, potassium sulfate 15 kg).

Fertilization method: first loosen the original furrow with a big plough or deep loosening shovel to a depth of 20-30 cm, then fill the water, and after the water seeps, filter the bottom fertilizer evenly into the furrow (applying 2 monopolies and 2 ridges). After the bottom fertilizer is filtered, break the original ridge and cover the bottom fertilizer, after covering the bottom fertilizer, filter the fertilizer again on the new ridge, then close the ridge to form a layered application of the bottom fertilizer, and then press it again with the mulch after closing the ridge. After pressing, cover with 70 cm wide plastic film, press the plastic film strictly, and prepare for transplanting.

Plant spacing and row spacing

1. Row spacing: each ridge is 65-70 cm, species 2 monopolizes 2 rows, and the line spacing is 2.1 meters.

2. Plant distance: 80-100 cm. Plant 350-500 plants per mu.

IV. Seedling raising and transplanting

1. Preparation of seedling tray

Choose 60cm*40cm*5cm or 60*40*8cm seedling tray with good water permeability or soilless sprout dish and other utensils, fill it with sand as big as rhubarb rice grain (medium sand), wash it with clean water to make pure sand (no soil), put it into bud tray 3-4 cm thick, ready for sowing.

2. Sprouting

At room temperature, put the seeds in the basin, soak the seeds in cold water for 8 hours, then remove the moisture and sticky substances from the seed surface with a coarse cloth or towel. In order to ensure the seeds germinate neatly, it is best to crack the seeds. Insert the seed into the open space in front of the back axle of the nail Clipper and hear a click. Then put the finished seeds on a slightly wrung (but not short of water) wet towel, 0.5-1.0cm thick, cover with a slightly wrung-out wet towel, and germinate at a constant temperature of 25-30 ℃ for 24-36 hours.

3. Sowing and raising seedlings

Put the seeds evenly (1.0cm*1.0cm) on a prepared sand table, cover it with 1.0cm thick pure sand (medium sand), and immediately water thoroughly. Put it indoors or in the greenhouse, no more than 30 ℃ in the daytime, no less than 18 ℃ at night, and the seedlings will emerge in about 3-4 days. Because the sand is permeable and easy to be short of water, watering again on the third day after sowing and watering can also cover the seedling tray with a layer of film and be removed immediately after emergence to preserve water and heat preservation. Water was watered once in the next 3-4 days and foliar liquid fertilizer was applied 5-7 days after emergence. When watering, put diammonium phosphate fertilizer in the water, and the concentration reaches 0.3% (that is, 10 jin of water, 0.3 yuan fertilizer). After watering, the nutrient water is watered every 5-7 days. The temperature is too high, the water is too big, too much fertilizer is easy to grow, so we should pay attention to control the overgrowth. Proper water control, temperature control, ventilation, seedling age 15-20 days. The seedlings should be refined 5-7 days before planting (seedling temperature 15-17 ℃). (when raising seedlings, you can raise more, more than 20% of the actual amount of seedlings, to prepare for seedling selection.) the above method is called cotyledon seedlings, also known as big bud seedlings. Save time, save money, low cost, easy to manage, 2 mu of land 1-2 plates will be enough. The large fruit watermelon cultivated in the open field passed steadily through 15 ℃ at atmospheric temperature and 10 ℃ at soil temperature, but the humidity conditions for seedling emergence and seedling growth should be ensured. Leave seed pits when sowing to prevent cotyledons from coming into contact with plastic film because of high temperature to burn the seedlings. Cover the plastic film immediately after sowing, and prevent the seedlings from roasting according to the situation and temperature of the seedlings.

4. Planting (transplanting)

When planting (first covered with plastic film and then planted), use a small soil shovel to dig a hole at a distance of 80-100cm (with plastic film) at a depth of 6-7cm. When transplanting, the seedlings were divided into different grades according to their size, and 2 seedlings were planted in each pit to select and retain the seedlings, and the seedlings were finished in 3-4 days. It is best to transplant on a windless sunny day in the morning to make it easy to survive. When transplanting, the root system of cotyledon seedlings should be extended, erect or lateral erect (tilted), and the root should not be curled, so as not to affect the root system and seedling growth. When cultivating the soil, it is appropriate not to expose the white roots. After cultivating the soil, gently compact the soil by hand, let the roots come into close contact with the soil, then immediately pour water through, and then cover the pit with 1cm thick fine soil after the water seeps, to prevent the formation of hard cover. Then cover the plastic film and compact the plastic film with soil to prevent it from being dried by the wind. After planting, keep the cotyledons and Hypocotyl 1.0-1.5 cm above the ground, and press each seedling with soil to prevent the plastic film from damaging the seedlings. When transplanting, the plant spacing staggered to lay the foundation for pruning and branching.

V. Field management

1. Pruning: three vines are pruned, leaving one strong main vine from the root and two strong lateral vines from the root, and the rest are pinched off in time. Pruning is best done around 11:00 to 4 p.m., and not on rainy days, to avoid wound infection and infection. If the vine is not straight, you must press it firmly with your hand.

2. Press the vine: generally press three. Press the first line when the main vine is 30-40 cm, and then press one at every 40cm (the side vine is the same as the main vine). When pressing the vine, you can use heavier soil or clods, and the weight of the soil is about 2 jin. The leaves were sprayed with fungicide 1-2 days before pruning to prevent wound infection during pruning. Dark pressure: the ground under the vine is dug a ditch with a depth of 5-10cm and a length of 10-20cm, the melon vine is buried with soil, and the leaves are exposed. It is more suitable for dry years according to the weather conditions, and the melon vine with overgrowth momentum can also be secretly pressed. Dark pressure should not be used in rainy and wet weather and years.

3. Artificial pollination: when the female flowers bloom, if they encounter foggy or rainy days, they should put on a rain-proof paper cap in the field in the afternoon of the first day when the female flowers bloom, and pick the male flowers from the ground at 5 o'clock the next morning and put them in the room where the temperature is suitable. When the female flowers bloom at 6-9 o'clock, go to the ground and put the petals of the male flowers on the back to reveal the pollen, gently rub it on the stigma of the female flowers, and then put on a rain-proof paper cap for the female flowers after pollination (the central purpose is not to let the stigma and pollen of the female flowers rain). In order to increase the rate of melon setting.

4. Melon: one melon per plant, generally choose the main vine, the 3rd-4th female flower of the main vine, and the third female flower of the lateral vine. When the young melon is seated, the remaining melon will be selected in time. In order to prevent only growing melons, you can use the method of falling melons, that is, the second melon grows to 3-4 days (steady) to remove the first melon, and so on, all the way to the ideal position and standard melon type.

When the young melon grows to the size of a goose egg, choose to keep the melon. Choose melon stalk thick and long, young melon skin color light green, no scar, melon type Zhou Zheng. As the selected melon, remove the rest.

The above is within the normal range, the special environment should be flexible to adjust the way of retaining melons.

For the watermelons sown and planted in spring in the north, no matter which pruning method, the melons with the first female flower in the main vine should be removed in time.

5. Topdressing and watering

1) watering and applying manure: when melon seedlings grow to 5-6 true leaves, one can be watered and fertilized before stretching according to soil moisture and seedling conditions.

If the water source is sufficient, it can be irrigated at a high speed in the trench between the two melon ridges, it should be watered thoroughly. Topdressing fertilizer before irrigation, 10 kg of urea and 10 kg of potassium sulfate per mu. Chase at the root side 20 cm far, 15 cm deep, eye-piercing.

2) fertilizing and watering the melon: when the female flower at the node of the melon is pollinated 7-12 days (when the young melon grows to the size of the goose egg), the melon must be fertilized and watered. 10 kg of urea and 10 kg of potassium sulfate per mu. Dressing grain fertilizer in rainy days and water fertilizer in dry days (urea and potassium sulfate are added to the water and dissolved, 20 cm away from the root side of the melon, eye-catching, 15 cm deep, each plant can not be less than 4 jin of water). If the soil is relatively wet, it can be watered less or not, it should be flexibly mastered according to the actual situation.

6. Pest control:

1) Prevention and control of blight and sudden fall disease at seedling stage.

When planting and watering, 70% methyl topiramate, 70% Fumei cream and 70% dimethazone wettable powder can be mixed into 500-800 times solution into the pit. Add the above three medicines and 1 jin to 500 jin of water.

2) Fusarium wilt control: the central diseased plants were found in the field (only 1-2 diseased plants). The roots were irrigated with 1500 times of Fusarium oxysporate solution and potassium dihydrogen phosphate, each plant was irrigated with 150ml (3-4 taels). At the same time, the nearby non-diseased plants are irrigated to the root. Before filling the root, remove the soil of the melon root by hand, see the white root, and then irrigate the root. After filling the root, it will be irrigated once a day for 5-7 days, generally 3-4 times can be controlled.

3) Prevention and control of anthrax: after anthracnose was found in the field, the fungus was used to kill the star 3000 times plus anthrax Fumei, potassium dihydrogen phosphate was added to every 30 jin of water, and foliar spraying was carried out. It is better not to rain 6-8 hours after spraying. If it rains within 6 hours after spraying, it should be sprayed immediately. Generally 5-7 days spray once, 3-4 times can be controlled. Or 50% methyl topiramate 25 grams + 50% tox 25 grams + 20 grams can be killed, mixed into 300 times liquid spray, spray once every 5-7 days, 2-3 times can be controlled.

4) aphid control: when ants are found on watermelon seedlings in the field, we should pay attention to check whether there are aphids. When there are a small number of aphids, we should immediately spray 40% omethoate 800x liquid, clean the liquid 800x, sweep 1000 times, spray once every 5-7 days, and control during the whole growth period. Liriomyza huidobrensis has been found in recent years, which should be controlled in time.