The staminate flowers are borne on a very long peduncle that rises above the foliage. The pistillate flowers have a short peduncle and a hairy ovary. The blossom persists much longer than that of Cucurbita . The flowers open during the night and remain open until the next afternoon. The nectar is not easily accessible.
Pollination probably takes place at or shortly after dawn if pollinators are available.
The flowers, being monoecious, cannot be self-pollinated. The pollen must be transferred from the staminate to the pistillate flower by an outside agent. He stated that the flowers are adapted to hummingbirds and smaller bees, although a species of bumble bee was observed visiting the flowers. Considering the flower odor and the fact that it is open during the night, nectar-collecting bats probably also contribute to its pollination. No recommendations on the use of insect pollinators on white- flowered gourds have been made, but the indications are plain that if a sizeable volume of fruit of this plant were desired the concentration of bees nearby would be worthwhile.