How to grow watermelon?

Recently, several farmers want to know about watermelon planting management, so today this article will briefly talk about the key points of watermelon planting management and technology from sowing to harvesting. Friends who grow watermelons can have a look and study together.

First, the time and temperature of watermelon planting

The sowing time of watermelon depends on the variety and temperature.

(a) from the watermelon varieties:

Early-maturing varieties harvested and marketed in early July generally start sowing around the middle and late March, middle and late-maturing watermelon varieties harvested and marketed from late July to early August generally start sowing around the middle and late April, and autumn watermelons harvested and marketed from September to 65438+1October generally start sowing around the end of June to mid-July.

(2) As far as weather temperature is concerned:

Because watermelon is a crop that prefers high temperature to low temperature, the seed germination needs a temperature above 15 (the optimum germination temperature is 25-28), the root growth needs a minimum temperature above 15, the seedling stage needs a minimum temperature above 22, and the flowering and fruiting period needs a minimum temperature above 25 and a large temperature difference between day and night to accumulate sugar.

Therefore, the earliest time for watermelon sowing (spring) should be when the soil temperature reaches above 15 (too low soil temperature will affect the germination and emergence of seeds), but the agricultural technology basket suggests that you wait until the soil temperature rises above 18-20 (when sowing, the soil temperature should not be lower than 15) before sowing, which will be more conducive to watermelon rapid and orderly.

Second, the choice of watermelon planting location

Although watermelon can be planted and grown in most soils, there are great differences in growth, yield and taste.

Generally speaking, the most suitable farmland soil type for watermelon planting and growth must meet the following requirements:

① Sandy soil or humus loam with strong permeability (hard and low-lying plots are not suitable for planting watermelons);

② The soil is loose and fertile with high organic matter content (the plot with shallow soil layer and poor soil quality is not suitable for planting watermelon);

(3) The plot is ventilated and sunny, with sufficient light (the plot with insufficient shade and light is not suitable for planting watermelon);

④ The soil acidity is weakly alkaline or neutral (plots with high acidity or salt content are not suitable for watermelon planting);

⑤ High terrain and convenient watering (high groundwater level, easy water accumulation, inconvenient watering, and plots with poor drainage are not suitable for growing watermelons);

⑥ No flowering and fruiting crops have been planted in the planting area for nearly 2-3 years (the best plot for 3-5 years has not been planted with watermelons) or the previous crops in the planting area are gramineous food crops (watermelons and melons cannot be planted in continuous cropping).

Thirdly, the selection of watermelon varieties and seeds.

Varieties and seeds used in watermelon planting must not be selected and used casually. We must consider the actual situation of soil fertility, climate conditions and planting patterns in watermelon planting areas. If the variety selection is improper, it will directly affect the growth, yield and quality of watermelon in the later stage.

(1) In the selection of watermelon varieties:

① Large melon varieties are recommended for plots with excellent soil water and fertilizer conditions, and small and medium melon varieties are recommended for plots with poor soil water and fertilizer conditions;

② In areas with low temperature, less light and rainy days, it is suggested to choose early-maturing varieties with short growth period and strong tolerance to shade and humidity. Watermelon varieties can be selected at will in areas with high temperature, sufficient light, sunny days and low humidity.

(3) Choose plot varieties with good soil, temperature, light and water conditions at will, but it is suggested that watermelon varieties planted in greenhouse should choose varieties that are resistant to damp and heat, low temperature and weak light, high flowering and fruiting rate and difficult to empty;

④ In plots where watermelons are often planted or need continuous cropping, it is suggested to choose varieties with strong disease resistance (especially those with high resistance to soil-borne diseases);

⑤ When watermelon is intercropped with other crops, it is suggested to choose varieties with low moisture tolerance, low branching ability, high fruit setting rate and early maturity.

If you plant early spring watermelons, then the agricultural technology basket suggests that you use very early-maturing or early-maturing watermelon varieties with low temperature tolerance, low light tolerance and high flowering and fruiting rate.

(2) In watermelon seed selection:

(1) Select new seeds whose seed age is about 1-2 years (the germination rate will be greatly reduced after sowing for more than 3 years);

(2) Select high-purity first-class high-quality seeds with seed purity not lower than 98-99% (if the seed purity is lower than 95-96%, the seed quality is poor);

③ Select high-quality seeds with water content below 12- 14% (if the water content exceeds 14- 15%, the seed quality is poor);

(4) Select high-quality seeds with seed germination rate above 95% (below 95% means poor quality, so you can do a simple experiment with the bought seeds);

⑤ Choose seeds with full seeds, uniform ears, smooth and clean seed coat, bright and clean seed surface, fragrant smell and no damp mildew, diseased spots, insect eyes or diseases (seeds with different sizes, shriveled seeds, rough seed coat, dull seed surface, damp mildew smell or diseases are all inferior seeds).

4. Seed treatment before watermelon planting

The shell of watermelon seeds is thick and hard, and direct seeding can easily affect the rapid water absorption and softening of seeds in the soil and the rapid germination and emergence, especially in spring when the soil temperature is low, which can easily cause problems such as rotten seeds, slow germination and uneven emergence, so we can treat the seeds slightly before sowing watermelon.

(1) seed drying and sterilization. Sow seeds 1-2 days continuously in sunny days 3-5 days before sowing, so as to awaken seeds to dormancy and reduce residual germs on the surface of seeds.

(2) Soaking seeds to accelerate germination. 2-3 days before sowing, the watermelon seeds are continuously stirred and scalded with hot water of 50-55 degrees for about 65438 05 minutes, and then taken out and soaked in warm water of 28-32 degrees for 6-8 hours. Finally, take out the seeds, wash them with clean water, cover them with clean wet gauze, and put them in a warm and humid environment of about 28 degrees for heat preservation, moisture preservation and germination acceleration, so that most watermelon seeds can be planted and germinated.

Five, watermelon sowing management and seedling management

(1) preserve heat and accelerate germination after sowing. Watermelon should be watered in seedbed or seedling pot in advance before sowing. After the water seeps into the ground, the exposed seed buds should be evenly sown upward (sowing first, then sowing). Then, you should spread a thin layer of soil on the seeds or cover them. Finally, plastic film should be covered for heat preservation and moisture retention to promote rapid germination of seeds. After watermelon is sown, the seedbed temperature should be kept at not less than 25 degrees before emergence (it is recommended to keep the seedbed at 28-30 degrees).

(2) cooling and strengthening seedlings after emergence. After watermelon seedlings grow to 1-2 true leaves, it is best to cool the seedbed by 1-2 degrees every day (keep the seedbed at 22-25 degrees), so that the seedlings can slowly and steadily adapt to the low temperature environment and prevent the seedlings from growing at high temperature, which is more conducive to enhancing the stress resistance of seedlings and improving the survival rate of seedling transplanting and planting in the later period.

(3) Transplanting and planting management. When the watermelon seedlings grow to 1 month, the height of the seedlings is 10- 15 cm, and 3-4 leaves 1 heart grow, the seedlings can be prepared for transplanting and planting in the field. In order to shorten the slow seedling stage and improve the survival rate of colonization, the agricultural technology basket suggests that everyone pay attention to the following points:

(1) 5-7 days before seedling emergence and transplanting, gradually increase ventilation, reduce the temperature of seedbed, harden seedlings at low temperature to promote roots and strengthen trees (gradually decrease to 18-20 degrees in the daytime and to 12- 15 degrees in the evening), and spray once every 3-5 days before seedling emergence.

(2) Watering the seedlings in advance, then taking soil blocks to protect the roots and raising seedlings, and classifying the seedlings according to the size and strength. When the soil temperature reaches 16- 18 degrees or above in sunny days, the seedlings are classified and planted.

③ It is suggested to dip the roots with hymexazol or microbial agents before transplanting (bare root planting), or to pour holes with hymexazol or microbial agents after transplanting (soil lump planting), which can not only reduce seedling diseases, but also promote rapid rooting and slow down seedling survival.

④ Reasonable density should be paid attention to when transplanting watermelon. There are about 1000 varieties of early-maturing watermelons per mu, and about 800 varieties of mid-late-maturing watermelons per mu. Note that planting too closely does not necessarily increase production and income.

Five, water and fertilizer management in watermelon growing period

Watermelon belongs to a crop type with long growth period and large amount of fertilizer. If it lacks fertilizer during the growing period, it will not grow well. As far as the demand for fertilizer in watermelon growth period is concerned, not only nitrogen (poor growth of stems and leaves lacking nitrogen, but also excessive nitrogen can easily crack melons, affect flowering and fruit setting, and reduce the eating quality of melons), phosphorus (poor growth of roots lacking phosphorus and poor flowering and pollination affect melons) and potassium (weak vines lacking potassium, poor disease resistance and stress resistance, which are not conducive to the expansion, coloring and sweetening of young melons) should be properly applied in watermelon growth period. At the same time, it is necessary to supplement trace elements such as calcium, magnesium and boron (calcium can strengthen roots and prevent fruit cracking, boron can improve flowering and fruit setting rate, promote young melons to expand rapidly in splinter cell, magnesium can fertilize green leaves and enhance photosynthetic manufacturing capacity).

Generally speaking, fertilizer should be applied 3-4 times-basic fertilizer (combined with adequate soil preparation), seedling-promoting fertilizer (applied lightly or not according to the seedling stage), rattan fertilizer (mainly nitrogen, supplemented by phosphorus and potassium), swollen melon fertilizer (applied with high potassium fertilizer after the young melon begins to expand) and foliar fertilizer (sprayed before and after flowering and during the young melon expansion period).

(1) base fertilizer

Combined with soil preparation, more than 3000 kilograms of decomposed farm manure or 200-400 kilograms of commercial organic fertilizer are applied per mu, and 50-60 kilograms of balanced ternary compound fertilizer of nitrogen, phosphorus and potassium are applied per mu (or 65438 in the north+05-20 kilograms of urea+20-25 kilograms of potassium sulfate+30-40 kilograms of calcium superphosphate or calcium magnesium phosphate in the south). For plots lacking trace elements in soil, 10- 15 kg of micro-fertilizer (or 1-2 kg of borax, zinc sulfate and magnesium sulfate respectively) can be added to the base fertilizer per mu, and15-can be applied per mu for soil diseases that are easy to die seedlings and dead trees, and for underground pests.

(2) fertilizer for promoting seedlings

If the water and fertilizer supply is good and the seedlings grow normally, there is no need to topdressing to promote seedlings. However, if the growth of watermelon seedlings is slow and the seedling vigor is weak after emergence, 2-3 kilograms of urea can be applied to each mu of mixed water (or sprayed twice with 0.3% urea solution, each time) 7- 10 days after transplanting or after seedlings grow 2-3 leaves.

(3) Stretching vine fertilizer

After watermelon enters the vine elongation stage (the seedling height is about 15 cm, and there are about 5-6 leaves), because of the need to grow vine stems and leaves and differentiate flower buds, watermelon grows vigorously at this time, and the demand for nitrogen, phosphorus and potassium is high. At this time, topdressing should be done in time. At this time, watering can be combined with the actual growth of watermelon seedlings, and about 10- 15 kg of balanced NPK compound fertilizer (plots with normal growth) or high nitrogen NPK compound fertilizer (plots with weak growth) can be applied per mu. If real-time conditions permit, 65,438+0-2 can also be sprayed with urea water+potassium dihydrogen phosphate+boron-containing foliar fertilizer.

(4) expanding melon fertilizer

When the first young melon sits on the watermelon vine, it is necessary to reapply the expanded melon fertilizer in stages. For the swelling fertilizer of young watermelon in the swelling period, it is recommended that you apply it twice in combination with watering. The first topdressing is performed when the young melon is about the size of an egg (the first expansion period of watermelon), the second topdressing is performed when the young melon grows to the size of a bowl (the second expansion period of watermelon), and the first topdressing is about/kloc-0.5 kg of balanced NPK compound fertilizer or 5-6 kg of balanced water-soluble fertilizer, and the second topdressing is performed.

(5) foliar fertilizer

Spraying foliar fertilizer in the middle and late growth period of watermelon can increase yield and improve quality by four or two kilograms. Generally speaking, potassium dihydrogen phosphate+boron-containing foliar fertilizer 1 time one week before flowering, and potassium dihydrogen phosphate+boron-containing foliar fertilizer 1-2 times after flowering. If watermelon leaves are yellow and premature aging, potassium dihydrogen phosphate can be used in combination with chelated iron. In addition, after the first batch of melons are harvested, it is suggested to spray 0.5% urea solution +0.3% potassium dihydrogen phosphate 1-2 times to quickly replenish nutrients for weak watermelon plants, promote watermelon to continue to accelerate flowering and fruiting, and promote yield increase.

(6) Water in the field

Under the premise of watering the bottom water before watermelon planting and properly fixing the roots and seedlings in time, the soil should be kept moist at the seedling stage, watered as little as possible after the seedlings survive, and kept moderately dry before flowering and fruiting, so as to promote the differentiation of strong roots and flower buds. Generally speaking, watermelon should be watered twice during its growing period. Pouring enough water at one time can meet the water demand of vigorous growth of stems and leaves in watermelon growing period. First, water the young melons frequently 7- 10 days before harvesting, so as to ensure sufficient and stable water supply for the expansion and development of the young melons (there can be no sudden dry and wet soil or drought and water shortage during the growth period of watermelons), and water should be controlled in time when watermelons enter maturity.

Six, watermelon seedling management during the growth period

(a) timely pruning tendrils

When the watermelon grows to 8- 10 leaves and the main vine grows to about 40-50 cm, the vine should be pruned in time in a sunny afternoon. When pruning watermelons, it is generally recommended to select the strongest two branches and branches from the 3rd to 5th section of the main vine on the basis of keeping the main vine robust, and then cut off all other lateral branches and vines. This pruning method is the most commonly used "three vines pruning method" in watermelon planting.

(2) Artificial pollination in bad weather

If watermelon can't be pollinated normally due to bad weather during flowering (such as rainy and humid weather), the agricultural technology basket suggests that people improve the pollination and seed setting rate of watermelon by artificial pollination. The specific operation is as follows: collect male flower pollen at the full flowering stage of watermelon, dip it with cotton swab and smear the stigma of female flower. The highest pollination quality of watermelon is around 8-9 am on sunny days (note: the artificial pollination time needs to be delayed 1-2 hours on rainy days).

(three) timely thinning flowers and fruits, reasonable thinning flowers and fruits.

Excessive flowering and fruit setting of watermelon is not only not conducive to high yield and income increase, but also easy to reduce production because of the small growth of watermelon, so we must pay attention to timely and appropriate thinning of flowers and fruits when planting watermelon.

After the watermelon blooms, the flowers should be thinned in time, and more plump and robust buds with early flowering and high fruit bearing rate should be selected, and the buds that are difficult to sit in the late flowering stage should be removed. Generally, 5-6 flowers are left on the robust branches, and all those dense, weak, small and diseased flowers should be removed. After the watermelon sits on the young melon (when the young melon grows to the size of an egg), the fruit should be thinned in time. Generally, 3-4 strong melons are selected from each strong branch, and all other weak, small, deformed and dense melons are thinned out. When the young melons grow to the size of the bowl, select 1-2 melons with reasonable position, correct melon type and healthy development from 3-4 melons selected in the early stage. Generally speaking, it is recommended to choose melons with the second and third most female flowers.

(4) reasonably control prosperity and avoid overproduction.

If watermelon grows vigorously during the growth period (especially after flowering and fruiting), it will affect the normal flowering and fruiting of watermelon, resulting in reduced production. Therefore, if watermelon grows vigorously, it should be controlled in time to inhibit the growth of stems and leaves and promote the development of flowers and melons.

For watermelon seedlings with luxuriant vines, the non-luxuriant seedlings can be controlled by gently pinching the vines in front of the young melons (when pinching the vines, the vines can be cracked and flattened to make a slight noise), and the over-luxuriant seedlings can be controlled by topping the main vines (pinching off the youngest segment slightly 2-3 cm). ) If artificial physical control can't control the growth of watermelon vine, then at this time, you can use paclobutrazol, chlormequat chloride, chlormequat chloride and other control drugs and spray 1-2 times for chemical control!