18" Wide Planters up to 218" Long (Oakland)

Seeking large, sturdy planters (or containers which can be creatively used as planters). These will be used on a parkway strip / curb edge to simultaneously beautify the neighborhood and deter people from parking on the sidewalk, so they should be something other than ceramic, not easily broken. Wood would be great. They don't need to be super-tall, but I need 18" of depth (slightly less is okay) from the street to the sidewalk, and I'm trying to fill a space 218" long. Please let me know what you've got, thanks! I can pick up most East Bay locations.