Years ago a friend called my attention to a long narrow planting of this aster around the corner from her home. Her neighbor had it planted all along the sidewalk, and it had formed a low mass which, when in bloom, was very handsome. At that time, I had plants of two of the best-known cultivars of this species, 'October Skies' and 'Raydon's Favorite', growing in my garden. But both of those were relatively taller than the plants along that sidewalk.
Eventually, self-sown seedlings began to appear in the garden. These were not so tall as the named cultivars. I like the one in the image above: a month ago you would not have expected it to have formed such a broad mass of bloom. I'll be spreading this one around the garden soon. And it makes a great companion for the Sternbergia lutea, doesn't it? (Look carefully, there is one peeking out in the upper left hand corner of the image).