There are certain plants (most flowers, in my opinion) that simply have more punch when grown in large masses. I'm not a big fan of "onesie-twosie" plantings, even with annuals. If I'm going to buy a flat of annual salvia to beef up the perennial bed, it's all going to go into one large drift. These few photos show how great a single simple flower can look when installed in quanity. As always, click to make them bigger if you want.
"Annabelle"
Hydrangea arborescens, one of my favorites, which consistently puts on a great show at this time of year, and isn't as fussy about water as some of the macrophyllas. These are fairly shaded at the Big House, but I have them at home in pretty intense sun, and they do just fine there, as well.
Plain old purple coneflowers. It seems the more they get ignored, the happier they are. I've not had great luck with all of the new fancy cultivars, but these guys just go on blooming for weeks!
Daylilies near the pool at the Big House. This one might be "Bumble Bee," but then again it could be any number of hundreds of different cultivars. They are so incestuous, I'm not sure that anyone really ever knows which daylily they truly are growing!
Annabelles again, below. This is a grouping that I really like, in a somewhat shady area. From November until January, we have camellia blossoms, then the Blue Star Creeper carpets the ground for a few weeks. After that, an ornamental crabapple puts on its show (it gets enough sun before the upper story trees leaf out), and then the Annabelles.