Magnolia sieboldii, or the Oyama magnolia, has fragrant, pure white, bowl-shaped, downward-facing flowers.

Description:
Magnolia sieboldii, commonly known as the Oyama or summer magnolia, is a Japanese native with fragrant, four inch wide, pure white, bowl-shaped, downward-facing flowers with red stamens. It is enchanting in from late spring to late summer to walk beneath the branches and look up into the open flowers. Also attractive are the light grey bark and the dark green leaves that turn golden yellow in autumn as the incredible pendulous, orange seed heads split open to reveal rows of deep purple seeds! Perfect for smaller scale landscapes. This is an understorey tree so it will do well in shaded gardens. Although most sites will list it as hardy to just zone 6, it has long grown happily in a windy, exposed site at the Minnesota Landscape Arboretum in zone 4.