Every garden lacking some form of structural component also lacks balance. This is simply because when the eye has only foliage and blossom to absorb with no solid elements upon which to rest it becomes weary and looks around for something more tangible upon which to light. Too much foliage or even an abundance of blossom without the counterpoint of a structural element will please us but briefly, whereas a garden comprised of both soft and hardscape continually refreshes the eye, allowing a prolonged enjoyment of each element and the combination of elements together.
The easiest way to experience both the problem of balance and its resolution is to find a planting containing no structure and place something solid within it. If you have a lushly planted perennial bed or a shrub border, for example, try placing an ornamental pot, a sculpture or even a large stone or piece of wood within it and see how it improves. Or take a very small space of plants, such as a groundcover bed and set something solid within it. Both the plants as well as the hard element will be seen to greater advantage. Even well planned and planted gardens will benefit from the addition of structural components. Many a beautiful perennial bed would be considerably more satisfying with some appropriate solidity added to it, as would a large expanse of lawn.
In the top the hardscape elements have been digitally removed. It is a pretty scene, but how long can you look at it? In the other image the eye can, and does return to the simple hardscape structures for rest and refreshment before wandering out over the infinitely complex detail in the planting.
Taken from the book”Hardscaping” by Keith Davitt