What's planted: Japanese iris is the thriller. White snapdragon, violet African daisy, red common geranium, and white 'Tidal Wave Silver' petunia are fillers. Pink and red ivy geraniums, dark red calibrachoa, and purple Lanai verbena are spillers.
Get the look: For an upscale window box (like the one above), have one custom made from rot-resistant wood, such as cedar. It will need painting and a metal liner inside to make it last. Check out less expensive alternatives at gardeners.com, kinsmangarden.com, plowhearth.com, and hooksandlattice.com, and see the Smith & Hawken collection at target.com.