I was surprised to discover that showy aster forms a large portion of our local forest understories. It spreads via rhizomes to form loose colonies of attractive large toothy-leafed plants, even in full shade, making it a suitable groundcover for shady gardens. This species flies under the radar until it gets a bit of sunshine, and only then will you see the lovely tall blue flowers that have rightly earned the moniker 'showy.' 
 
 
 
Showy aster will need extra watering if it is in full sun, but can tolerate substantial drying down in the shade, occasionally going completely dormant before reappearing with fall moisture. In shady spots, plant with heart-leaf arnica, smooth blue aster, and shade-tolerant shrubs such as prickly currant and wild rose.