When I design gardens, I keep one thing in mind. Planting so that every season there is some sort of color. This not only adds interest to the garden but also keeps things from getting boring. Adding color through plants is also a great way to try out different colors in your landscape that are not permanent. This way if you end up getting tired of a certain color, then that plant is far easier to replace then having to repaint a wall.
You are not limited by your options and in fact you can mix and match colors depending on your taste. A good rule of thumb is to pick at least two plants that bloom most of the year and add pops of color throughout the seasons. The colors you add depends on what colors you fancy.
On that note this video is all about the top 3 plants to add for fall color.
If you are interested in other seasonal plantings then click on the appropriate season.
Winter seasonal planting.
Spring seasonal planting.
Summer seasonal planting.