The trough plants as a whole are such spring bloomers that their fall colors always seem to surprise me. This trough holds a dwarf chamaecyparis, a dwarf iris, a dianthus, a variegated sedum, geranium 'Ballerina', and a dracocephalum. Yes, it sits directly on the drainage grate at the bottom of my driveway, right in front of the garage. Why not put a trough on top, right?
That's sedum cauticola in the square planter behind the center trough. It happily shares space with a large quince. The trough on the right holds a lot of lewisias and is probably the leanest planting mixture that I've tried. The plants seem to love it though.