Toad Lilies or Tricertis have been one of my favorite late summer / fall flowering perennials.  The one above is a purple flowering variety with a yellow edge on the green leaves.  I have one Samurai that produced a true blue flower last year, hopefully it will be the same this year, maybe I'll see next week.  Toad Lilies produce small delicate orchid-like flowers in a variety of cool colours with a few yellow ones, many have dark spots or markings on them.  Most varieties have a solid green leaf but I find that I am most interested in ones with varigated leaves giving a bit more interest to the shade garden.  I have a number of varieties that started to bloom last week and should keep on blooming until near the end of October maybe into November depending upon the seasons weather progression. 

Zones 6 - 8, some varieties might survive in a protected zone 5 area. / Dry to moist soil / part sun to shade. / Medium growth rate. / Blooms in late Summer to Fall.