Here’s a plant that you should consider for long season interest. Sturdy 2′ stems are clothed with delicate fine needled foliage, reminiscent of Amsonia hubrictii, gradually forming stands 2-3′ across. Vernonia lettermanii remains attractive all summer, and in early September, clusters of purple aster blossoms top the stems, inviting myriads of monarch butterflies. Picture this little gem planted with Sedum ‘Maestro’, Anemone ‘Honorine Jobert’ and Calamintha nepetoides and you will no doubt pleased by this end of the summer vignette.
Just about all of us can grow Vernonia lettermannii . Native to the Ozarks and found in rocky flood plains, this compact species of Ironweed is very tolerant of hot dry locations, yet can withstand brief periods of flooding. This means it is quite adaptable to soil types. It can be grown in gardens ranging from zones 4-9, adding one more plant to cold climate palettes.