What are the causes of poor fruit set in watermelons?
Watermelon is favored and loved by many people in our country, and market demand is growing ever larger, with the planting area expanding accordingly. However, many beginners run into the same problem during cultivation: poor fruit set. Poor fruit set can seriously affect watermelon yields and growers' income. So what exactly are the causes of poor fruit set in watermelons? Why do watermelons set fruit poorly? Let's take a look below!
1. Temperature
Watermelon is a crop with separate male and female flowers, pollinated by bees and other insects. But if rainy, low-temperature weather occurs during flowering, it will affect pollination and fertilization, leading to poor fruit set. In open-field cultivation, raindrops falling on the stigma cause the pollen to absorb water and burst, making pollination impossible. A high-temperature environment causes the watermelon vines to grow wildly and excessively, affecting the fruit's nutrients and water supply, and leading to poor fruit set.
2. Light
Watermelon is a fruit that requires a great deal of light, needing high light intensity and long hours throughout the entire growing period from sowing to maturity. If light is too weak, the internodes of the watermelon become long and the leaves become large and thin, making strong photosynthesis impossible; ultimately, flowers and fruits drop due to insufficient nutrients, and the final sugar content of the fruit also declines, resulting in poor quality.
3. Water
Watermelon has particularly strong drought tolerance, and the environment in which it grows requires relatively dry soil and air. If the relative humidity in the air is above 60%, watermelon growth becomes stunted, the fruit set rate declines, and pests and diseases are more likely to occur. But if it is below 50%, it will affect watermelon growth and also harm pollen germination to some extent. The soil's water-holding capacity needs to be maintained between 65% and 75%.
4. Density
Planting density should not be too dense or too sparse. Too dense means each watermelon cannot absorb nutrients evenly, and it is impossible to ensure that all watermelons can grow and develop normally; they may even develop deformed. Moreover, field aeration is too poor, seriously affecting the growth of underground stems and leaves, resulting in poor fruit set. Too sparse causes watermelons to have excess nutrients, leading to tillering that affects normal fruit development.
5. Nitrogen fertilizer
Many friends use excessive amounts of nitrogen fertilizer in order to increase watermelon yield and quality, but this backfires. Although nitrogen fertilizer promotes growth, excessive application causes the watermelon vines, leaves and stems to grow excessively, creating an imbalance between vegetative growth and reproductive growth. The fruit then suffers from malnutrition, leading to poor fruit set or even flower drop and fruit abortion.
Alright, the above are several main causes of poor fruit set in watermelons. Of course, there are more besides these, such as pests and diseases. If watermelon pests and diseases are not prevented in time, or diseased fruits are not handled, the pests and diseases will harm the growth of the fruit and also cause flower drop and poor fruit set in watermelons. So I hope everyone will pay more attention in normal times and reduce or eliminate this situation as much as possible.