Blossoms that wilt and fall off the plant before setting fruit may be affected by a number of factors.
For some plants, such as cucurbits, the flowers appearing first are male, which naturally drop. If later
fruiting flowers drop in large numbers, it may be due to insufficient pollination. Other factors involved
may be extremely high or low temperatures, insufficient soil moisture, or smog.
and falling of eggplant blossom due to cold weather