In my case, a little bit of internet research showed that small boxwood plants would be a good choice for my window boxes. Aside from giving the facade a slightly formal and green year-round look that I like, they work well in containers, are ultra hearty, can survive the cold temps and don't require lots of maintenance. I feel ridiculously proud of their survival and now can be found carefully watering and fussing over them (for a total of 10 minutes - its a pretty small garden!) each weekend.
The lesson? If you've been unsuccessful with plantings in the past but are interested in adding some green growing things to your life (and no, that old cheese in the back of your fridge doesn't count) don't fear, just be sure to go with the easy, hearty stuff! We all need to start somewhere and stacking the deck in your favor when it comes to choosing plants is a wise way to go.
Here are a good selection of posts on practically fool-proof plant projects to get you going, build your confidence and teach those of us with (formerly!) non-green thumbs a thing or two:
As shown above, top row, left to right:
Bottom row, left to right:
Images: Main image: Leah Moss, Gallery images: as credited in linked archive posts