1. Apply fruit-expanding fertilizer: Topdress with high-potassium and high-calcium water-soluble fertilizer, and spray medium and micronutrient fertilizers such as iron, boron, and manganese at the same time. 2. Apply vegetable oil: add 3-4 drops of soybean oil or vegetable oil near the main root. 3. Spray diluted sugar solution: Spray diluted sugar solution on the leaves. 4. Temperature difference between day and night: Maintaining the temperature difference between day and night at 16-18°C will help increase the sugar content of melons.
Methods to quickly sweeten melons
1. Apply expanding fruit fertilizer
When the first batch of melons grow to the size of eggs and lose their hair, Topdress 15-20 kilograms of high-potassium and high-calcium water-soluble fertilizer, combined with watering and hole application, and spray medium and micronutrient fertilizers such as iron, boron, and manganese to promote fruit enlargement and the accumulation of dissolved substances and sugars in the fruit.
2. Apply vegetable oil
When the melon grows to the size of a fist, use a wooden stick with a diameter of 1.5 cm to make a small hole of 12 cm 2 cm away from the main root, and drip in 3- 4 drops of soybean oil or rapeseed oil, fill it with soil, and pour a small amount of water every 3-5 days, which will help increase the sweetness of the fruit.
3. Spray dilute sugar solution
During the expansion stage of melon, you can use 300 times dilute sugar solution to spray the leaves 2-3 times or water the roots 2-3 times. It is conducive to the accumulation of sugar. Pay attention to controlling the concentration of sugar solution, otherwise the fruit will rot and wilt.
4. Temperature difference between day and night
A large temperature difference between day and night is conducive to the accumulation of photosynthetic products, namely sugar. During the melon fruit expansion period, the temperature in the greenhouse should be maintained at 32-35°C during the day. The temperature at night is 15-18°C, and the temperature difference between day and night is maintained at 16-18°C, which is conducive to the increase of sugar content in melons.