Paulownia

Paulownia tomentosa or Imperial Tree is a fast-growing tree with a very elegant and large habit, perfect for a spacious garden. The flowering occurs in spring and blooms on the still naked branches in magnificent clusters of mauve bell-shaped flowers. Afterwards, the foliage appears with opulent 15-25cm (6-10in) diameter leaves. Once they fall in autumn, particularly decorative dry fruits persist, split shells resembling little birds with wide-open beaks.

Paulownia tomentosa is a tall tree that easily reaches 12m (39ft) in height, but if pruned as a coppice, it is possible to maintain a low height like a bush. The leaves will then be even larger, but unfortunately, you won't have any flowering. The 'Fast Blue' variety has a more conical habit and a flowering with lilac shades. 

Paulownia tomentosa thrives in a sunny or semi-shaded position. It appreciates any type of soil as long as it is deep and well-drained, but it fears the wind that breaks its branches.