Eric again wants to know what advice Alex might offer our audience about these eye catching plantings. Well it is a different growing environment than having 2 feet of rich soil. One of the most important questions one must ask themselves, and they need to be honest with themselves, is - Are you willing to water them? Because the soil isn't that deep they do require more of a commitment to water frequently. When putting a window box together it's important to build them with as much soil as they can handle without it being too heavy.
Alex has done a great job with the vertical elements in these window boxes, the Veronica and geranium look great. Alex thinks window boxes should feel very full and exuberant and a great way to do that is by giving it height. Height is important. For trailing elements he has used petunias, verbena and calibrachoa and they look fantastic too. Often when thinking about window boxes we think about the trailing, cascading or spilling elements. But consider height as well, it is important. And don't compromise on the number of plants in a window box. All of these things add to the beauty of a window box.