If you analyze successful garden designs, most fall into one of the three basic patterns described below, though clever planting and variations on the themes almost always result in individual designs.
Circular themes are very effective at disguising the predictable shape of a rectangular garden. Circular lawns, circular patios, and circular beds are all options and you only need to overlap and interlock a few circles to create a stylish garden. Plants fill the gaps between the curved areas and the straight edges.
The diagonal theme is a device that creates a sense of space by taking the eye along and across the garden.
The rectangular theme is what most people design even though they may not make a conscious effort to do so. The device is effective if you want to create a formal look, or wish to divide a long, narrow garden up into smaller sections.