Transitions of materials in the landscape should be minimized. At each transition of ground plane material, an opportunity for migration of the material (typically organic or inorganic mulch) is presented. The transitions between the materials also present potential maintenance obstacles – namely landscape edging and material migration.
Landscape edging has the tendency to come out of the landscape from kids playing, wildlife or landscape maintenance processes. There are also additional opportunities for unwanted plants (weeds) to show up at these transitions, which decreases the aesthetic quality of the landscape and increases maintenance costs. The image on the right illustrates multiple ground plane materials in a small landscape area.
There are occasions when changes to the ground plane may present an opportunity for emphasis or for functional purposes. Many times, transitions in the ground plane occur in drainage swales, often between buildings, where smaller organic or inorganic mulch may migrate easily with flowing water.