What causes pumpkin fruit drop

Pumpkin fruit drop is a problem often encountered during pumpkin cultivation, seriously affecting pumpkin yields and causing farmers to suffer great losses. So, why do pumpkins drop fruit?

1. Why pumpkins drop fruit

1. Excessive nitrogen fertilizer and rainwater cause excessive vegetative growth, with stems, leaves and main and side vines all growing more vigorously than the fruit, resulting in insufficient nutrients during the fruiting period and leading to fruit drop.

2. Failure to harvest the first fruit in time causes the second fruit to drop.

3. Keeping too dense a stand of plants is not conducive to air circulation and light penetration, which is also a cause of fruit drop.

2. What to do about pumpkin fruit drop

1. Regulate the relationship between vegetative growth and reproductive growth. When vegetative growth is too vigorous and no female flowers have formed after the main vine has extended to the 12th node, the apical dominance should be weakened to promote the transformation from vegetative growth to reproductive growth. The methods are: (1) Changing the leader: when the main vine sets no fruit, cut off the main vine just before the leaf node closest to the front that bears a secondary vine; the closer this secondary vine is to the roots, the better, so that fruiting shifts from the main vine to the secondary vine. (2) Coiling: coil the tip of the main vine into a loop and tie it with string. (3) Twisting: appropriately twist and bruise the tip of the main vine to impair the transport function of the vascular bundles. (4) Cutting part of the roots: carry out a deeper cultivation to cut some of the roots.

2. For flower and fruit drop caused by too many female flowers, thin out some of the flowers and fruits.

3. Artificial supplementary pollination: 8—10 in the morning is the most suitable time, when the pollen is already mature; pick a vigorous male flower, remove the petals, and gently smear the anther onto the stigma of the female flower; at this time the stigma secretes mucus that holds the male flower's pollen. One male flower can pollinate 2—3 female flowers in succession. After pollination, cover with a leaf or the corolla to prevent rain from washing the pollen off. Where conditions permit, release bees to pollinate during the pumpkin flowering season; 2—3 hives per hectare is sufficient.

4. Plant at a reasonable density; keeping 12,000—18,000 plants per hectare is advisable. Early-maturing varieties can be planted more densely, late-maturing varieties more sparsely, which favors ventilation and light penetration, improves the fruit-setting rate, and can also help prevent the occurrence of Phytophthora blight.