Veronica kiusiana is a beautiful perennial Speedwell from Japan, and while it is brand new to my garden,  I have never encountered a Veronica, person or plant, that I haven't liked.   Veronica kiusiana grows to two and a half feet tall with jagged, bright green leaves and long spikes of china blue flowers.  The arching, nodding flowers tips are reminiscent of Lysimachia clethroides (Gooseneck Loosestrife).  Of all the Veronicas I have grown through the years, this is by far the nicest.  I would say I have a guest that I want to linger for a very long while.  This lovely and graceful perennial plant likes moisture-retentive soils and sun/part shade in Zones 6-10.  Quarts.