Hortus Botanicus Amsterdam was the first garden
in the Netherlands to bloom Victoria, in 1859. To celebrate
the 150th anniversary, they grew a spectacular V. 'Longwood
Hybrid' in their outdoor pond. It produced 31 flowers over the
season which ended in October. With a climate about equal to
USDA Zone 6, the water was heated to 26-30 C (79-86 F).