Lilium formosanum (Formosa Lily)

Yes, you need one of these or a few hundred scattered around the garden.  Coming in at up to 6' tall this lily will tower over most things in the garden but being so narrow it takes up little to no space at all.  There can be up to ten 6-10" pure white flowers on each plant!  They also provide great winter interest in the garden as the seed pods persist at the top of the stems all winter.  And if you like to collect and save seeds this plant will be one of your favorites just for the shear number you can dump out of one seed pod!