One last note on creating an island bed: finish it off well by edging it. Whether you’re using a landscape edging or a narrow, crusty moat, the edging will prevent the sod from creeping into the bed and give it a professional finish. Emphasize your edge with stones or plants.
This is a good example of traditional island beds. Each bed is in proportion to the space available. Note that the plants in each bed are well balanced and interesting from every angle. The front bed borders a driveway with the plants positioned to give the best view from the driveway entrance. Each bed contains a different combination of plants and each is neatly bordered with simple moats. With the several beds, an English-style promenade is created.