This is Peruvian Sage (Salvia discolor), also known as “Andian Sage.” Fairly rare even in its native Peru, the plant grow long white stems with leaves that are green on one side and white on the other. The end of the stem is a series of deep purple flowers the color of blackberries with a scent that’s a blend of sage and currants.

It propagates easily, but is a little tender when it comes to cold, so they do need to be sheltered more than some of the native sages. Here’s the plant in front of several other Salvias:

Black Peruvian Sage (Salvia discolor) in late summer

The one complaint I have is that it’s super sticky from base to flower, so even brushing the plant will end up with some of it stuck to you.