According to the University of Illinois Extension, "The rose is ... 35 million years old. In nature, the genus Rosa has some 150 species spread throughout the Northern Hemisphere... Garden cultivation of roses began some 5,000 years ago, probably in China. During the Roman period, roses were grown extensively in the Middle East. They were used as confetti at celebrations, for medicinal purposes, and as a source of perfume." Cultivated roses which had many more petals than wild roses came to Europe in the 1700’s.
One rose garden that blew me away was Queen Mary’s Rose Garden in Regent’s Park. It is the largest rose garden in London with 12,000 roses across 400 varieties. Planted in the 1930's in blocks, I have never seen so many roses in one place. The color and fragrance will knock you out.
Next time you are in London, this is a great spot to visit.
See more examples of gardenesque gardens here.