The mysterious behavior of Victoria flowers has stirred people’s imagination ever since this giant water lily was introduced into cultivation in the mid-nineteenth century. Native to South America, Victoria evolved into two distinct species: Victoria amazonica inhabiting the backwaters of the Amazon and its tributaries and Victoria cruziana found further south, along Río Paraguay and Río Paraná.
The huge flowers of the Victoria reveal much about the ancient origin of waterlilies as some of the earliest flowering plants on earth. They open at sunset, spreading numerous white petals above water, providing a safe landing platform for nocturnal scarab beetles, which are notoriously clumsy fliers. Beetles are attracted to the flowers by the nutritious starchy appendages on which the insects feast. The appendages are tucked along the walls of a spacious floral chamber hidden below the many whorls of petals. The pollen grains delivered by the beetles fall to the floor of this chamber, where they germinate sending pollen tubes to fertilize ovules embedded in the spiny ovary underneath.
While the flower spreads its petals in the evening its temperature rises up to 20 degrees Fahrenheit above the ambient. This rare phenomenon facilitates the diffusion of the flower’s delightful and seductive fragrance, which guides the incoming beetles into the floral chamber and improves chances for successful pollination by keeping the insects warm and active throughout the night. In the morning, Victoria folds back its petals, closing the entrance to the floral chamber, effectively trapping the beetles inside. When the flower opens again the following evening, the most magical transformation takes place. The petals that were pure white the previous night are now variously suffused pink and purple.
The color change is an indication that the flower is entering its male phase of development. The stamens—the male parts of the flower that circle the entrance to the floral chamber and were inactive on the first night—now shed pollen on the beetles scrambling out of the flower. Free at last, the beetles carry a new load of pollen to the next flower that opens that evening, thus assuring cross-pollination. Following the release of the beetles the flower closes for the second time and sinks under water never to be seen again. This mesmerizing ritual is repeated in the backwaters of South American rivers every night and has done so for millions of years.
The history, biology, and allure of the Victoria will be explored in my upcoming book, Victoria: The Seductress, which will be released in March of 2013. Visitors to Longwood can experience the mystery and the majesty of Victoria during a new exhibit produced by Longwood Gardens, opening in 2013. While visiting Longwood this summer, please be sure to spend some time in our Waterlily Garden, which reaches peak bloom in September, and enjoy the seduction of the Victoria for yourself.
UPDATE (May 2, 2013): Victoria: The Seductress is now available for sale online at shop.longwoodgardens.org