Gardens need structure to give them interest, and to be pleasant to look at.                                                                  

 Whether you are planning on a very formal garden with a central focal point, or an informal english garden that is rather wild in nature and the mixture of plants, adding some type of border gives the eye a place to start and end.            



You can use hardscape materials such as a wall or fencing, or you can use border plants.  I feel that if you choose to use border plants, something that is green year round is the correct selection.  It will give your garden structure in all seasons.  Be sure to select a plant that will remain low and uniform in appearance to give it the neat look you are after.