Nothing says summer like a gaily blossomed window box.
This box requires moderate woodworking skills. Simplify construction by leaving off the box's fretwork; instead nail three mitered strips of crown molding underneath the 1 x 2 that rests atop the box. Or simply leave off the fretwork. The materials list is based on a 5-foot-wide box. If you want a wider or narrower box, adjust the amount of lumber.
1. Choose your materials. Make it with cedar or redwood, so the completed box will stand up to weathering and watering. Using galvanized screws instead of nails also adds to the life of the box.
2. Preserve the window box even longer by inserting a plastic liner or fashioning a liner of sheet metal.
3. Finish. If the box is made entirely of the same wood, you can allow it to weather. Or paint the finished box inside and out with an exterior oil-base primer and exterior latex paint (white or deep forest green would be especially attractive). Paint the metal brackets to match the building.