What Causes Hollow Watermelon? Detailed Explanation of Prevention Methods
Watermelon is one of the seasonal fruits of summer, with high water content and a sweet taste, deeply loved by people. However, sometimes when we cut open a watermelon we find it hollow. What is going on? In fact, hollow watermelon is also quite a headache for growers. How can it be prevented? Let's take a look at the detailed explanation below.
1. Low temperature
The suitable growth temperature for watermelon during the flowering and fruit-setting period is between 25-30 degrees, and the lowest average temperature is between 20-21 degrees. After the watermelon sets fruit, the cells begin to separate and the fruit begins to expand. However, if the temperature is too low when the watermelon sets fruit, the cell division rate slows down, resulting in an insufficient number of cells. Then, as the temperature rises again, the rind begins to expand, but there are not enough flesh cells to fill the space inside the fruit, thus causing the hollow phenomenon.
Prevention method: During the flowering and fruit-setting period of watermelon, temperature regulation must be done well to keep the temperature within the suitable range, neither too high nor too low, so that it can grow and develop normally.
2. Cloudy and rainy weather with insufficient light
The growth and development of the fruit cannot be separated from nutrients. If there is a lot of cloudy and rainy weather and little light during the fruit development period, the photosynthesis of watermelon leaves will be affected, resulting in insufficient synthesis of nutrients. This weakens the cell division of the flesh and affects the volume of the flesh. However, when the fruit lacks nutrients, the rind still grows normally, so a hollow forms. In addition, excessive application of nitrogen fertilizer and excessive watering can cause excessive vegetative growth of the plant and a closed, shaded field, which also affects photosynthesis. Moreover, the growth of stems and leaves competes with the fruit for water and nutrients, which can also lead to hollowing.
Prevention method: During long periods of cloudy and rainy weather, drain water in time to reduce field humidity, so as to avoid excessive vegetative growth of stems and leaves and prevent leaf photosynthesis from being affected and nutrient synthesis capacity from being weakened. At this time, foliar fertilizer spraying can be adopted to maintain nutrients. At the same time, attention should be paid to the application of nitrogen fertilizer. To prevent excessive vegetative growth of the plant, excessively growing stems and leaves should be removed in time to avoid competing with the fruit for water and nutrients.
3. Water shortage
During the fruit development process, not only sufficient nutrients are needed, but also enough water. If there is a serious water shortage during the fruit expansion period, the fruit cells likewise cannot expand and a hollow forms.
Prevention method: During the fruit expansion period, water must not be lacking. Water frequently to keep the soil moist, but large-scale flooding irrigation is not suitable, so as to avoid fruit cracking. Drip irrigation can be used for watering.
4. Delayed harvest
If the watermelon is not harvested in time after ripening, nutrients and water will flow back, so the fruit will form a hollow because it loses water and nutrients. This phenomenon is relatively common in varieties whose fruits develop quickly.
Prevention method: Harvest in time after the fruit ripens, so as to avoid the backflow of water and nutrients and cause unnecessary losses.
The above is an introduction to the causes of hollow watermelon and prevention methods. We hope it can help you. If you want to learn more related knowledge, please keep following us.