Mexican Sage

 

Mexican Salvia (Salvia leucantha) is a great fall blooming accent. It starts blooming in August typically and continues on till frost cuts it back. The small white flowers are outshone by the fuzzy purple calyxes which hang on after the flowers pass. This is a carefree perennial, requiring very little water. Although it is beautiful outdoors, don't try to cut it for an indoor arrangement. (It smells like cat pee). A clump increases in size through the years and can be divided by cutting through the clump with a sharp shovel. Stem cuttings also root.
You can see the Mexican salvia in the background of the top picture.