Perennial Plant of the Year 2016
Japanese Anemone
Zone 5 - 9
Gorgeous single, white, poppy-like blooms with sunny yellow cone-like centres.  Long flowering late summer and into the fall.  HEIGHT:  90-125 cm  SPREAD:  60-90 cm
Japanese Anemone are outstanding perennials for the late summer and fall garden.  Slow to establish they will  however spread to create a large patch.  Carefree and low maintenance, they generally perform best in part shade and moist soil, although I have found they also do quite well in full sun and dryish soil.
1 gallon size
Image courtesy of Darwin Plants