Why Pumpkins Drop Before They Grow Big and the Latest Solutions
Pumpkin is a common fruiting vegetable with many ways to eat it. Once ripe, it can be used to make porridge, soup, and pumpkin cakes, while the immature young fruit is also a delicacy. However, when growing pumpkins, the problem of small fruit can occur. When the pumpkin grows to about the size of a fist, it wilts, drops, and dies on its own. What is going on here? Let's find out together.
1. Poor Pollination
Under high-temperature conditions, pollination of pumpkins is affected. When the temperature exceeds 32 degrees, as the temperature rises, the floral organs develop abnormally and pollen function declines. When the temperature reaches as high as 40 degrees, pollen germination and pollen tube elongation drop significantly, pollen life is short, and fertilization is hindered. If the female flower is not pollinated, the pumpkin will gradually stop growing and may even drop with a bitter taste. In addition, rainy weather during flowering can also affect normal pollination. The main reason is that heavy rain affects the development of the ovary and floral organs, and rainwater easily washes away the pollen on the stigma of the female flower, causing the pollen to lose its germination ability, making pollination difficult to complete and causing fruit drop.
Control method: For high-temperature weather, when planting, choose varieties with strong parthenocarpic ability, high-temperature resistance, and a high fruit-setting rate. During high temperatures, set up shade nets, or spray water mist to cool down.
2. Improper Fertilizer and Water Management
Applying a large amount of nitrogen fertilizer before pumpkin fruit set, along with heavy rain before fruit set, can easily cause the pumpkin vines to grow excessively when fertilizer and water are sufficient. By the time the pumpkin sets fruit, the branches and leaves have consumed a large amount of nutrients, causing the young fruit to lack nutrition, fail to grow, and finally drop off.
Control method: Strengthen fertilizer and water management. Especially before flowering and fruit set, apply little or no fertilizer and water, and especially control the application of nitrogen fertilizer. When the plant grows excessively, a chlormequat chloride solution can be used to drench the roots to inhibit vegetative growth. In the middle growth stage, heavy fertilization should be applied before the rows close. The amount of fertilizer should be determined according to the plant's development and soil fertility. If the growing point of the vine is thick and upturned and the leaf color is dark green, it is not suitable to fertilize. If the leaf color is light green or the leaves turn yellow, topdressing should be applied in time.
3. Pests and Diseases
Disease threats during the flowering and fruit-setting stages of pumpkins can also cause pumpkins to fail to grow big and to drop. For example, gray mold can cause pumpkin flowers and fruits to drop.
Control method: Pest and disease control must be done carefully. For plants with pests and diseases, apply the right treatment. Aphids can be controlled with imidacloprid; powdery mildew can be controlled with difenoconazole, tebuconazole, pyraclostrobin, and other agents; gray mold can be controlled with procymidone, pyrimethanil, iprodione, and others; plants that have wilted should be pulled out in time.
The above is an introduction to what to do when pumpkins fail to grow big and drop. We hope it helps you. For more related knowledge, please stay tuned to us.