Some call it 'China Rose'

When you stretch your hand wide open with all the fingers as spread out as possible, you would still be hard pressed to beat this one's spread.

They are huge and very good for you.

If you dry the flowers of this plant and then take a few and steep them for a few minutes in boiling water, they make a drink called Jamaica, which is a tea served over ice, ruby red color in appearance, and a bit tart. I add sugar or honey to mine.