Portland's Rose Society was founded in 1889, and the city's collection of hybrids, floribundas, and grandifloras has been growing ever since. In 1917 the International Rose Test Garden opened as a testing ground for new varieties of roses. Some of its first plantings were rose refugees from Europe during World War I. Today, over 10,000 plants and 550 species slope towards the city's downtown horizon.
The International Rose Test Garden is the oldest continuously operating public rose test garden in the United States. It was founded in 1917 on the hills of Washington Park in Portland, Oregon.
