OMU News

Sep 20, 2022

A grand flower opening: Observation of Night-blooming Tropical Water Lilies

On September 2, 2022, the “Observation of Night-blooming Tropical Water Lilies” was held at the OMU Botanical Gardens in Katano. This year’s event was the 11th observation, which is usually held annually, but this was the first one in three years to proceed.

23 visitors participated in the Observation of Night-blooming Tropical Water Lilies. The Botanical Gardens—usually close at 4:30 pm—but stayed open for the event from 5-8:30 pm so that visitors could watch the flowers bloom.

Tropical water lilies begin to open soon after dusk, in this case 7 pm, and remained blooming until around 9 am the next morning. The flowers bloom for three nights, during which they display their brightly colored flowers, and emit a strong fragrance that attracts the nocturnal insects that pollinate them.

Expert commentary and a demonstration of the lilies’ specially adapted biology were provided by Associate Professor Satoshi Koi, from the Graduate School of Science. Due to the weather forecast, which predicted rain, the lilies were moved into a greenhouse, where Professor Koi explained the internal structures of the lilies. He also gave the visitors the opportunity to examine the cross section of a flower and the underside of a lily pad.

“It was fantastic to see the petals opening in the dim light; I think that this was a moment that greatly changed my impression of the plant, which I rarely see in motion,” Professor Koi commented. “We were happy to be able to experience the interesting features of tropical water lilies, such as their special structure for living on the surface of water and their clever pollen dispersal system.”



Professor Koi, dissecting the lily flower
to reveal the internal structures


Professor Koi, speaking about
the tropical water lilies’ amazing adaptations


OMU Botanical Gardens
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