When do we start growing watermelon seedlings?

Now is the seedling stage for many plants. In most cases, watermelon seedling raising is also arranged in spring. The cultivation cycle is usually about 30 days, which provides them with sufficient time to develop strong root systems and sufficient leaves, laying a good foundation for subsequent transplanting and growth. Let’s learn when to start growing watermelon seedlings.

When do we start growing watermelon seedlings?

The best time to grow watermelon seedlings usually falls between mid-March and early April. The advantages of this period are relatively abundant rainfall and moderate humidity. At the same time, the temperature gradually warms up and will not drop sharply to a cold state. These conditions are conducive to the germination of watermelon seeds and the healthy growth of seedlings. If this period is missed, the climatic conditions may no longer be suitable for growing watermelon seedlings.

Watermelon seedling cultivation method

1. Soil preparation

Choose soil that has not been used to grow melons within 5-7 years as the seedling bed soil, and make sure the soil is loose, moist and fertile. Organic fertilizer should account for about 50% of the volume of the bed soil, and add appropriate amounts of urea and superphosphate to meet the seedling stage's demand for nitrogen and phosphorus fertilizers.

2. Seed treatment

Since the watermelon seed coat is thick and hard and absorbs water slowly, you can use the method of blanching the seeds, that is, blanching the seeds with boiling water. This can both disinfect and soften the seed coat and accelerate water absorption. The specific operation is: pour boiling water while stirring, stop stirring after 10 seconds, add cold water to lower the water temperature to 50℃, and then soak in 30℃ water for 8-10 hours. You can also soak it in warm water at 20-30℃ for 10-12 hours, but this will not have a disinfecting effect. During the soaking process, the seeds should be washed 1-2 times and rubbed to remove mucus and debris on the surface and promote water absorption and germination.

3. Seedling cultivation method

Early cultivation usually uses hotbed seedlings to protect the root system and avoid the problem of seedling stiffness caused by root damage. In tropical areas such as Yunnan, direct seeding may be used for early cultivation. Before sowing, soak the seeds in 50℃ warm water for 12-24 hours, then wrap them with moist gauze and germinate them at 25-30℃. After 3-4 days, the seeds can be sown after they break.

4. Grafting technology

In watermelon cultivation, grafting is a common method to improve disease resistance and adaptability. Commonly used grafting methods include top grafting, approach grafting and root cutting grafting, among which top grafting is the simplest. When grafting, the rootstock should be sown 3-5 days earlier than the scion (watermelon). The rootstock should be sown in a nutrient pot and the scion should be sown in a plug tray or sand bed. When the cotyledons of the rootstock emerge from the soil, the watermelon can be germinated and sown.

In general, now is the critical period for watermelon seedling cultivation. If the environment in your area meets the temperature conditions for watermelon seedling cultivation, you can proceed as soon as possible.