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Young fruit falling off may

Young fruit falling off may be due to several factors, usually about pollination. Even though pollinators may visit the flowers, the fruit can develop for a time but then stop. A flower is viable for only about a day, and pollinators must visit it about 7 times for best pollination results. If the fruit aborts or becomes misshapen, the pollinators may not have transferred enough pollen; perhaps not enough visited the flower due to bad weather conditions (too cool or hot, too windy or rainy).

 

High heat (above 90F) for several days may hurt the pollen, so that the plant eventually rejects the growing fruit. In this case, you may get more flowers later, for further fruits to develop in better weather.

 

If you have a seedless watermelon type, you'll need to plant a seeded type nearby that blossoms at the same time for proper pollination and fruit set.

 

Watermelons should be watered deeply, about 1 to 2 inches per week, as well as more during a drought or high heat. Be consistent especially during fruit development. Drip irrigation is best. For overhead irrigation, water during the morning so that the leaves can dry during the day, to discourage diseases.

 

Too much water will make a bland tasting melon. Too little water may stunt the plant and cause misshapen fruit, but it doesn't sound like your plants are lacking water.