Do Watermelon Seedlings Need Pinching? Master the Correct Topping Method

Whenever the scorching summer arrives, we think of eating watermelon; its flesh is sweet, its juice is abundant, and it can cool us down and relieve the heat. So, do you know, during the watermelon growing process, do watermelon seedlings need their heads pinched off?

1. Do watermelon seedlings need their heads pinched off?

Watermelon seedlings need their heads pinched off at the appropriate time. When the watermelon enters the swelling stage, the vine ahead of the fruit should be properly suppressed so that it does not grow vigorously, otherwise it will consume nutrients and affect the swelling of the fruit. The specific operation is to pull the vine ahead of the fruit back, coil it beside the watermelon, and pinch off the vine tip along the way.

2. What are the cultivation techniques for watermelon?

1. Site selection

It is best to choose sandy loam with deep soil, loose and fertile texture, and convenient drainage and irrigation, and to cultivate on plots where no cucurbit crops have been grown within 5 years on dry land or within 3 years on paddy fields.

2. Land preparation and fertilization

Before winter, deep-plow the watermelon field and let the soil freeze into clods, then prepare the land in good time before transplanting. The watermelon field should have three ditches in a complete system, so that the field dries as soon as the rain stops and the soil is loose with a level bed surface. The base fertilizer should be mainly high-quality organic fertilizer and cake fertilizer, supplemented by inorganic fertilizer, generally accounting for 60%-70% of the total fertilizer application; nitrogen, phosphorus, and potassium should be reasonably matched; and trace fertilizers should be applied to the soil or sprayed according to the situation of deficiency. Use raised-bed planting, with wide beds 4-4.5 m and narrow beds 2.0-2.5 m. On wide beds, plants can be set out on both sides of the bed with the vines climbing toward each other, or set out in the middle with the vines climbing to both sides; on narrow beds, plants are set out on one side with the vines climbing to one side.

3. Planting

Early-maturing watermelon seedlings are about 1 month old and can be planted once they have grown 2-3 true leaves. Mid-maturing watermelon seedlings can be planted at 20-25 days old, and late-maturing watermelon seedlings at 7-10 days old. Plant 2 rows on wide beds and 1 row on narrow beds. For small-fruit watermelons grown in greenhouses with vertical trellises, plant 1500-1800 plants per mu; for ground-trailing cultivation, use three-vine or four-vine pruning and plant 600-750 plants per mu. For medium and large watermelons, generally plant 650-700 plants per mu, and for grafted seedless watermelons, plant 300-400 plants per mu. Cover with film while transplanting; the film width should be no less than 80 cm, and covering should achieve a fine, level bed surface, with the film pressed tightly against the bed surface, all around sealed firmly, and the holes in the film sealed tightly with fine soil.

4. Pruning and vine pressing

Generally, the three-vine pruning method is used. When the main vine has 8-9 leaves, keep the main vine and two robust side vines, and remove all the other secondary and tertiary vines. Pruning should not be done on cloudy and rainy days to prevent the spread of disease. When the vines grow to about 50 cm, press the vines with soil together with pruning; afterward, press once more every 3-4 nodes, for a total of 2-3 pressings per vine, and arrange the vines evenly.

5. Fruit setting

Choose the 2nd or 3rd female flower on the main vine or the 1st or 2nd female flower on a side vine for fruit setting. To ensure fruit setting at a suitable node, artificial pollination should be used in low-temperature or cloudy and rainy weather to help preserve flowers and fruits. After the fruit has set firmly, break up the soil under the young fruit until fine and pat it level, make it into a slope shape, then place the young fruit along the slope and arrange the young fruit and the vine in a straight line. When the fruit has grown fully, turn the fruit in good time. When turning, rotate in one direction, about 1/3 each time.

6. Topdressing

When the young fruit grows to the size of an egg, apply fruit-swelling fertilizer according to the plant's growth vigor, generally 15-20 kg per mu of 45% nitro-sulfur-based or potassium sulfate-type controlled-release fertilizer.

7. Water

After fruit setting, a sufficient water supply should be ensured. From 7-10 days before harvest, watering should be avoided so that the fruit accumulates sugar.

8. Harvest

Harvesting is best done in the morning. Generally, early-maturing varieties are harvested about 30 days after pollination, mid-maturing varieties about 35 days, and late-maturing varieties about 40 days. How quickly the fruit matures is affected by temperature, light intensity, and time; it is best to note the date at pollination, and when maturity is expected, take a sample fruit, cut it open, measure its sugar content and taste it, and after confirming maturity, harvest in batches according to the markers.

Pinching the tips of watermelon seedlings helps improve fruit quality, but it should also be decided according to the actual situation; if there are not many branches on a single vine, it does not need to be done.