Spiranthes cernua 'Chadds Ford' is another of the hardy orchids, a native American even, and I totally forgot it when I was writing the other day about orchids. It likes sun, though it will grow in light shade and will grow just about anywhere in the US since I looked it up and it says zones 3-9. It has low green foliage and 12 inch flower spikes which bloom in September and have a smell something like vanilla, though maybe a little more flowery. Smells are so hard to describe. It likes moisture since in the wild it prefers bogs. We have grown it both in boggy conditions and just in the border and it did well in both places, though the one that was more damp certainly increased faster. It is easy to grow and will form a colony, slowly, by underground runners. I think this plant was 2 or 3 years old when the picture was taken, so you can see that it makes a showy small clump rather quickly.
Rereading all that I just wrote I'm not sure it makes a lot of sense, but I spent all afternoon outside in the sun, so I'll blame that. Fall cleanup is definitely underway and hopefully will be finished before I need mittens to work outside.